Recycling machinery of integrin coupled with focal adhesion turnover via RAB11-UNC13D-FAK axis for migration of pancreatic cancer cells.

BACKGROUND: Recycling of integrin via endosomal vesicles is critical for the migration of cancer cells, which leads to the metastasis of pancreatic cancer and devastating cancer-related death. So, new diagnostic and therapeutic molecules which target the recycling of endosomal vesicles need to be developed. METHODS: Public databases including TCGA, ICGC, GSE21501, GSE28735, and GENT are analyzed to derive diagnostic and therapeutic targets. To reveal biological roles and underlying mechanisms of molecular targets, various molecular biological experiments were conducted. RESULTS: First, we identified UNC13D's overexpression in patients with pancreatic cancer (n = 824) and its prognostic significance and high hazard ratio (HR) in four independent pancreatic cancer cohorts (TCGA, n = 178, p = 0.014, HR = 3.629; ICGC, n = 91, p = 0.000, HR = 4.362; GSE21501, n = 102, p = 0.002, HR = 2.339; GSE28735, n = 45, p = 0.022, HR = 2.681). Additionally, its expression is associated with the clinicopathological progression of pancreatic cancer. Further biological studies have shown that UNC13D regulates the migration of pancreatic cancer cells by coupling the exocytosis of recycling endosomes with focal adhesion turnover via the regulation of FAK phosphorylation. Immunoprecipitation and immunocytochemistry showed the formation of the RAB11-UNC13D-FAK axis in endosomes during integrin recycling. We observed that UNC13D directly interacted with the FERM domain of FAK and regulated FAK phosphorylation in a calcium-dependent manner. Finally, we found co-expression of UNC13D and FAK showed the poorest survival (TCGA, p = 0.000; ICGC, p = 0.036; GSE28735, p = 0.006). CONCLUSIONS: We highlight that UNC13D, a novel prognostic factor, promotes pancreatic cancer progression by coupling integrin recycling with focal adhesion turnover via the RAB11-UNC13D-FAK axis for the migration of pancreatic cancer cells.

Effect of saline irrigation temperature difference on postoperative acute pain and hypothermia during biportal endoscopic spine surgery.

BACKGROUND: Recently, enhanced recovery after surgery (ERAS) protocols have attracted attention; they emphasize on avoiding intraoperative hypothermia while performing lumbar fusion surgery. However, none of the studies have reported the protocol for determining the temperature of saline irrigation during biportal endoscopic spine surgery (BESS) procedure. This study evaluated the effectiveness of warm saline irrigation during BESS in acute postoperative pain and inflammatory reactions. MATERIALS AND METHODS: Fifty-five patients who underwent BESS procedure were retrospectively analyzed for the incidence of perioperative hypothermia (< 36oC), postoperative inflammatory factors (white blood cells (WBC), erythrocyte sedimentation rate (ESR), C-reactive protein (CRP), interleukin-6 (IL-6), serum amyloid A (SAA)), and clinical outcomes (back visual analog scale (VAS) score, postoperative shivering). The patients were divided into the warm and cold saline irrigation groups. RESULTS: Hemoglobin, WBC, ESR, creatine kinase, and creatine kinase-muscle brain levels did not significantly differ between the warm and cold saline groups. The mean CRP, IL-6, and SAA levels were significantly higher in the cold saline group than in the warm saline group (p = 0.0058, 0.0028, and 0.0246, respectively); back VAS scores were also higher with a statistically significant difference until two days postoperatively (p < 0.001). During the entire procedure, the body temperature was significantly lower in the cold saline irrigation group, but the hypothermia incidence rate significantly differed 30 min after the operation was started. CONCLUSIONS: Using warm saline irrigation during BESS is beneficial for early recovery after surgery, as it is associated with reduced postoperative pain and complication rates.

Shoulder Traction as a Possible Risk Factor for C5 Palsy in Anterior Cervical Surgery: A Cadaveric Study.

Background and Objectives: Many risk factors for postoperative C5 palsy (PC5P) have been reported regarding a "cord shift" after a posterior approach. However, there are few reports about shoulder traction as a possible risk factor of anterior cervical surgery. Therefore, we assessed the stretched nerve roots when shoulder traction was applied on cadavers. Materials and Methods: Eight cadavers were employed in this study, available based on age and the presence of foramen stenosis. After dissecting the sternocleidomastoid muscle of the cadaver, the shoulder joint was pulled with a force of 2, 5, 8, 10, 15, and 20 kg. Then, the stretched length of the fifth nerve root was measured in the extra-foraminal zone. In addition, the same measurement was performed after cutting the carotid artery to accurately identify the nerve root's origin. After an additional dissection was performed so that the superior trunk of the brachial plexus could be seen, the stretched length of the fifth and sixth nerve roots was measured again. Results: Throughout the entire experiment, the fifth nerve root stretched out for an average of 1.94 mm at 8 kg and an average of 5.03 mm at a maximum force of 20 kg. In three experiments, the elongated lengths of the C5 nerve root at 8 kg and 20 kg were 1.69/4.38 mm, 2.13/5.00 mm, and 0.75/5.31 mm, respectively, and in the third experiment, the elongated length of the C6 nerve root was 1.88/5.44 mm. Conclusions: Although this was a cadaveric experiment, it suggests that shoulder traction could be the risk factors for PC5P after anterior cervical surgery. In addition, for patients with foraminal stenosis and central stenosis, the risk would be higher. Therefore, the surgeon should be aware of this, and the patient would need sufficient explanation.

Evaluation of the efficacy and safety of conventional and biportal endoscopic decompressive laminectomy in patients with lumbar spinal stenosis (ENDO-B trial): a protocol for a prospective, randomized, assessor-blind, multicenter trial.

BACKGROUND: Recent studies on biportal endoscopic spine surgery in patients with lumbar spinal stenosis have reported good clinical results. However, these studies have been limited by the small sample sizes and use of a retrospective study design. Therefore, we aim to compare the efficacy and safety of biportal endoscopic decompressive laminectomy with those of conventional decompressive laminectomy in a multicenter, prospective, randomized controlled trial. METHODS: This study will include 120 patients (60 per group, aged 20-80 years) with 1- or 2-level lumbar spinal stenosis, who will be recruited from six hospitals. The study will be conducted from July 2021 to December 2024. The primary outcome (Oswestry Disability Index at 12 months after surgery) will be evaluated through a modified intention-to-treat method. The secondary outcomes will include the following: visual analog scale score for low back and lower extremity radiating pain, EuroQol 5-dimensions score, surgery satisfaction, walking time, postoperative return to daily life period, postoperative surgical scars, and some surgery-related variables. Radiographic outcomes will be analyzed using magnetic resonance imaging or computed tomography. All outcomes will be evaluated before the surgery and at 2 weeks, 3 months, 6 months, and 12 months postoperatively. This protocol adheres to the Standard Protocol Items: Recommendations for Interventional Trials (SPIRIT) guidelines for reporting of clinical trial protocols. DISCUSSION: It is hypothesized that the efficacy and safety of biportal endoscopic and conventional decompressive laminectomy will be comparable in patients with lumbar spinal stenosis. The results of this trial will provide a high level of evidence for the efficacy and safety of the biportal endoscopic technique in patients with lumbar spinal stenosis and facilitate the development of clinical practice guidelines. Furthermore, the results of this study may indicate the feasibility of the biportal endoscopic technique for other types of spinal surgery. TRIAL REGISTRATION: The ENDO-B trial is registered at Clinical Research Information Service (CRIS, cris.nih.go.kr ) (KCT0006057; April 52,021).

Self-folding nanostructures with imprint patterned surfaces (SNIPS).

A significant need in nanotechnology is the development of methods to mass-produce three-dimensional (3D) nanostructures and their ordered assemblies with patterns of functional materials such as metals, ceramics, device grade semiconductors, and polymers. While top-down lithography approaches can enable heterogeneous integration, tunability, and significant material versatility, these methods enable inherently two-dimensional (2D) patterning. Bottom-up approaches enable mass-production of 3D nanostructures and their assemblies but with limited precision, and tunability in surface patterning. Here, we demonstrate a methodology to create Self-folding Nanostructures with Imprint Patterned Surfaces (SNIPS). By a variety of examples, we illustrate that SNIPS, either individually or in ordered arrays, are mass-producible and have significant tunability, material heterogeneity, and patterning precision.

Self-reported eating speed in relation to non-alcoholic fatty liver disease in adults.

PURPOSE: Non-alcoholic fatty liver disease (NAFLD), known to be related to insulin resistance, has been the focus of intensive research efforts due to its increasing prevalence and clinical significance. Rapid eating behavior is another emerging health issue associated with insulin resistance. We aimed to clarify the correlation between self-reported eating speed and NAFLD, both known to be related to insulin resistance. METHODS: A cross-sectional study was conducted during routine medical checkups on 7,917 consecutively enrolled participants. Anthropometric, biochemical, nutritional, and social parameters were checked. The self-reported eating speed per their usual meal (<5, 5-10, 10-15, and more than 15 min) was recorded by a registered dietitian. RESULTS: The faster eating groups had a higher proportion of NAFLD, and the grade of NAFLD was advanced. After controlling for anthropometric, cardiometabolic, social, and nutritional parameters, the fastest eating group (<5 min) showed an increased risk of NAFLD compared with the lowest eating speed group (≥15 min) both in total [odds ratio (OR) 1.81, 95% confidence interval (CI) 1.24-2.63] and the participants with BMI < 25 kg/m(2) (OR 1.79, 95% CI 1.22-2.61). As the self-reported eating speed increased, the risk of NAFLD also increased in total and those with BMI < 25 kg/m(2) (P for trend <0.001). CONCLUSIONS: Fast eating is associated with an increased risk of the presence and grade of NAFLD in Korean adults, especially those with BMI < 25 kg/m(2), since presence of overweight or obesity may be overwhelming the effect on NAFLD.

Clinical Outcome and Changes of Foraminal Dimension in Patients With Foraminal Stenosis After ACDF.

STUDY DESIGN: Prospective study. OBJECTIVE: To determine the clinical outcome and change in foraminal dimension after anterior cervical discectomy and fusion (ACDF) and to investigate the correlation between clinical outcome and foraminal dimension. SUMMARY OF BACKGROUND DATA: No previous studies have evaluated the correlation between clinical outcome and foraminal dimension after ACDF in foraminal stenosis. METHODS: A consecutive series of 44 patients (114 foramina) undergoing planned ACDF due to foraminal stenosis were studied. Clinical outcomes included the neck pain visual analogue scale (VAS), arm pain VAS, neck disability index (NDI), subjective improvement rate, dysphasia, and donor site pain. Radiologic outcomes included anterior and posterior disk height, height of foramen and anterior-posterior diameter of the foramen, and the Cobb angle of the fusion segment. Foraminal dimension was calculated. RESULTS: The neck pain VAS decreased from 3.7 preoperatively to 2.3 postoperatively. Likewise, arm pain VAS decreased from 7.2 to 2.2, and NDI decreased from 31.0% to 17.2%. Mild dysphasia occurred in 3 patients. There was no donor site pain. Subjective improvement rate was 79.3%. The anterior disk height increased from 4.75 mm preoperatively to 7.01 mm postoperatively. Likewise, posterior disk height increased from 4.11 to 5.74 mm, height of foramen increased from 7.30 to 9.25 mm, anterior-posterior diameter of foramen increased from 3.56 to 4.92 mm, dimension of foramen increased from 20.50 to 35.58 mm, and segmental angle of fusion segment increased from 2.87 to 4.95 degrees. Posterior disk height was positively correlated with foraminal dimension. An increased segmental angle was negatively correlated with foraminal dimension. The foraminal dimension was negatively correlated with the arm pain VAS. CONCLUSIONS: ACDF in cervical foraminal stenosis was a useful surgical option to improve clinical outcomes and widen the foraminal dimension. The foraminal dimension was negatively correlated with the arm pain. Restoration of posterior disk height was necessary to widen the foraminal dimension, whereas increased lordosis of the fusion segment did not help to widen the foraminal dimension.

Opto-mechanical analysis of nonlinear elastomer membrane deformation under hydraulic pressure for variable-focus liquid-filled microlenses.

Nonlinear large deformation of a transparent elastomer membrane under hydraulic pressure was analyzed to investigate its optical performance for a variable-focus liquid-filled membrane microlens. In most membrane microlenses, actuators control the hydraulic pressure of optical fluid so that the elastomer membrane together with the internal optical fluid changes its shape, which alters the light path of the microlens to adapt its optical power. A fluid-structure interaction simulation was performed to estimate the transient behavior of the microlens under the operation of electroactive polymer actuators, demonstrating that the viscosity of the optical fluid successfully stabilizes the fluctuations within a fairly short period of time during dynamic operations. Axisymmetric nonlinear plate theory was used to calculate the deformation profile of the membrane under hydrostatic pressure, with which optical characteristics of the membrane microlens were estimated. The effects of gravitation and viscoelastic behavior of the elastomer membrane on the optical performance of the membrane microlens were also evaluated with finite element analysis.

Herniated intervertebral disk induces hypertrophy and ossification of ligamentum flavum.

STUDY DESIGN: In vitro experiment using degenerated human ligamentum flavum (LF) and herniated intervertebral disk (IVD). OBJECTIVES: To investigate the role and effect of degenerated and herniated IVDs on LF hypertrophy and ossification. SUMMARY OF BACKGROUND DATA: Spinal stenosis is caused, in part, by hypertrophy and ossification of the LF, which are induced by aging and degenerative process. It is well known that degenerated IVDs spontaneously produce inflammatory cytokines. Therefore, we hypothesized that degenerated IVD may affect adjacent LF through secreted inflammatory cytokines. METHODS: LF and herniated lumbar IVD tissues were obtained during surgical spinal procedures. LF fibroblasts were isolated by enzymatic digestion of LF tissue. LF cell cultures were treated with disk supernatant from herniated IVDs. Secreted cytokines from IVD tissue culture were detected by enzyme-linked immunosorbent assay. After analysis of cytotoxicity, DNA synthesis was measured. Reverse transcription-polymerase chain reaction for mRNA expressions of types I, II, III, V, and XI collagen and osteocalcin, and histochemical stains were performed. RESULTS: Supernatant from tissue culture of herniated IVD showed increased production of interleukin-1α, interleukin-6, tumor necrosis factor-α, prostaglandin E2, and nitric oxide compared with disk tissue culture from traumatic condition. There was no cytotoxicity in LF cells treated with disk supernatant from herniated IVDs. There was significant increase in DNA synthesis, upregulation in mRNA expression of types III, XI collagen and osteocalcin, whereas variable expression pattern of type I and V, and strong positive stains for Von Kossa and alkaline phosphatase in LF cultures with disk supernatant. CONCLUSIONS: Degenerated and herniated IVDs provide an important pathomechanism in hypertrophy and ossification of the LF through inflammatory cytokines.

Thermal stability analysis of nitrile additives in LiFSI for lithium-ion batteries: An accelerating rate calorimetry study.

Although lithium-ion batteries (LIBs) are extensively used as secondary storage energy devices, they also pose a significant fire and explosion hazard. Subsequently, thermal stability studies for LiPF6- and LiFSI-type electrolytes have been conducted extensively. However, the thermal characteristics of these electrolytes with thermally stable additives in a full cell assembly have yet to be explored. This study presents a comprehensive accelerating rate calorimetry (ARC) study. First, 1.2-Ah cells were prepared using a control commercial LiPF6 electrolyte and LiFSI with a specific succinonitrile additive and ethyl-methyl carbonate as a thermally stable electrolyte additive. The kinetic parameters involved in heat generation and their effects on the thermal properties of the ARC module were analyzed from the heat-wait-seek (HWS), self-heating (SH), and thermal runaway (TR) stages. The results indicate that the addition of a succinonitrile additive to the LiFSI electrolyte lowers the decomposition temperatures of the solid electrolyte interface (SEI) owing to polymerization with Li at the anode, while simultaneously increasing the activation energy of reaction temperatures at SEI between the separator and the electrolyte. The maximum thermal-runaway temperature decreased from 417 °C (ΔH = 5.26 kJ) (LiPF6) to 285 °C (ΔH = 2.068 kJ) (LiFSI + succinonitrile). This study provides key insights to the thermal characteristics of LiPF6 and LiFSI during the self-heating and thermal runaway stages and indicates a practical method for achieving thermally stable LIBs.

Long-Term Incidence of Adjacent Segmental Pathology After Minimally Invasive vs. Open Transforaminal Lumbar Interbody Fusion.

STUDY DESIGN: Retrospective cohort study. OBJECTIVE: To compare the incidence of adjacent segmental pathology (ASP) following minimally invasive (MI) vs open transforaminal lumbar interbody fusion (TLIF) and to identify factors linked to ASP requiring reoperation. METHODS: This retrospective study reviewed the outcomes of patients who underwent MI-TLIF or open TLIF. Radiographic ASP (RASP) was evaluated using X-ray imaging to distinguish between degenerative changes, spondylolisthesis, and instability in the adjacent spinal segment. Clinical ASP (CASP) was assessed with the visual analog scale score for leg and back pain and the Oswestry disability index. Patient data were collected 1, 2, 5, and 10 years postoperatively. The timing and frequency of ASP reoperation were analyzed. RESULTS: Five years postoperatively, the RASP rate was 35.23% and 45.95% in the MI-TLIF and open TLIF groups. The frequency of CASP differed significantly between the MI-TLIF and open TLIF groups at 1 year postoperatively. The rates of RASP, CASP, and ASP necessitating reoperation were not significantly different 10 years postoperatively. Cranial facet violation significantly affected ASP in both groups. In the open TLIF group, preoperative adjacent segment disc degeneration significantly influenced ASP. CONCLUSION: The RASP rate at 5 years postoperatively and the CASP rate at 1 year postoperatively differed significantly between groups. There was no difference in the rate of ASP requiring reoperation. Cranial facet violation is a crucial driving factor for ASP after both surgical procedures.

Risk Factors and Characteristics of In-Hospital Falls After Spine Surgery: A Retrospective, Single-Center Cohort Study in the Republic of Korea.

Background: Falls after orthopaedic surgery can cause serious injuries, which lengthen hospital stays and increase medical expenses. This has prompted hospitals to implement various fall-prevention protocols. The aims of this study were to determine the incidence of in-hospital falls after spine surgery, to analyze the overall risk factors, to discern factors that have a major influence on falls, and to evaluate the effectiveness of the fall-prevention protocol that we implemented. Methods: This was a retrospective, single-center study including patients who underwent spine surgery from January 2011 to November 2021 at the National Health Insurance Service Ilsan Hospital (NHISIH) in Goyang, Republic of Korea. Reported falls among these patients were examined. Patient demographics; surgery type, date, and diagnosis; and fall date and time were evaluated. Results: Overall, 5,317 spine surgeries were performed, and 128 in-hospital falls were reported (overall incidence: 2.31%). From the multivariable analyses, older age and American Society of Anesthesiologists (ASA) score were identified as independent risk factors for in-hospital patient falls (multivariable adjusted hazard ratio [aHR] for age 70 to 79 years, 1.021 [95% confidence interval (CI), 1.01 to 1.031]; for age ≥80 years, 1.035 [1.01 to 1.06]; and for ASA score of 3, 1.02 [1.01 to 1.031]). Similar results were seen in the subgroup who underwent primary surgery. Within 2 weeks following surgery, the highest frequency of falls occurred at 3 to 7 days postoperatively. The lowest fall rate was observed in the evening (6 to 10 p.m.). Morbidities, including rib, spine, and extremity fractures, were recorded for 14 patients, but none of these patients underwent operative treatment related to the fall. The NHISIH implemented a comprehensive nursing care service in May 2015 and a fall protocol in May 2017, but the annual incidence rate did not improve. The fall rate was higher after thoracolumbar surgeries (2.47%) than after cervical surgeries (1.20%). Moreover, a higher fall rate was observed in thoracolumbar cases with a greater number of fusion levels and revision spine surgeries. Conclusions: Patients with advanced age, more comorbidities, a greater number of fusion levels, and revision surgeries and who are female are more vulnerable to in-hospital falls after spine surgery. Novel strategies that target these risk factors are warranted. Level of Evidence: Prognostic Level III. See Instructions for Authors for a complete description of levels of evidence.

Association of Functional Gastrointestinal Disorders with Adolescent Idiopathic Scoliosis.

Numerous adolescents diagnosed with adolescent idiopathic scoliosis (AIS) often manifest symptoms indicative of functional gastrointestinal disorders (FGIDs). However, the precise connection between FGIDs and AIS remains unclear. The study involved adolescents drawn from sample datasets provided by the Korean Health Insurance Review and Assessment Service spanning from 2012 to 2016, with a median dataset size of 1,446,632 patients. The AIS group consisted of individuals aged 10 to 19 with diagnostic codes for AIS, while the control group consisted of those without AIS diagnostic codes. The median prevalence of FGIDs in adolescents with AIS from 2012 to 2016 was 24%. When accounting for confounding factors, the analysis revealed that adolescents with AIS were consistently more prone to experiencing FGIDs each year (2012: adjusted odds ratio (aOR), 1.21 [95% confidence interval (CI), 1.10-1.35], p < 0.001; 2013: aOR, 1.31 [95% CI, 1.18-1.46], p < 0.001; 2014: aOR, 1.24 [95% CI, 1.12-1.38], p < 0.001; 2015: aOR, 1.34 [95% CI, 1.21-1.49], p < 0.001; and 2016: aOR, 1.35 [95% CI, 1.21-1.50], p < 0.001). These findings suggest that AIS is correlated with an elevated likelihood of FGIDs, indicating that AIS may function as a potential risk factor for these gastrointestinal issues. Consequently, it is recommended to provide counseling to adolescents with AIS, alerting them to the heightened probability of experiencing chronic gastrointestinal symptoms.

Sacroiliac Joint Degeneration After Lumbar or Lumbosacral Fusion Surgery-A Comparative Study of the Number of Fused Segments and Sacral Fusion.

OBJECTIVE: In this study, we aimed to investigate whether multi-segment fusion or fusion-to-sacrum increases sacroiliac joint (SIJ) pathology compared with single-segment fusion or a non-fused sacrum. METHODS: This study included 116 patients who underwent lumbar or lumbosacral fusion and were followed up for 2 years. The patients were classified into single-segment fusion (n = 46) and multi-segment fusion (more than two levels, n = 70) groups and then reclassified into the non-fused sacrum (n = 68) and fusion-to-sacrum groups (n = 48). Preoperative and postoperative radiographs were used to evaluate radiographic parameters, and computed tomography (CT) was used to evaluate SIJ degeneration. Low back pain (LBP) was assessed using a visual analog scale (VAS, 0-10). Baseline and postoperative values were compared using a paired sample t-test. RESULTS: LBP VAS scores significantly differed at 6 months (single-segment fusion, 3.04±1.88; multi-segment fusion, 4.83±2.33; P < 0.001) and 2 years postoperatively (single-segment fusion, 3.3±2.2; multi-segment fusion, 4.78±2.59; P = 0.094). There was no significant difference in SIJ degeneration, as assessed by CT scan, between the 2 surgical groups: 14 (30%) and 19 (27%) patients in the single-segment and multi-segment (P = 0.701) fusion groups, respectively. The LBP VAS scale showed comparable differences at 1 (non-fused sacrum, 3±2.18; fusion-to-sacrum, 3.74±2.28; P = 0.090) and 2 years postoperatively (non-fused sacrum, 3.29±2.01; fusion-to-sacrum, 4.66±2.71; P = 0.095). CT scan revealed that 18 (26%) and 15 (31%) patients in the non-fused sacrum and fusion-to-sacrum groups, respectively, developed SIJ arthritis; however, there was no significant intergroup difference (P = 0.574). CONCLUSIONS: SIJ degeneration occurs independent of the number of fused segments or sacrum involvement.

Accelerated fusion dynamics by recombinant human bone morphogenetic protein-2 following transforaminal lumbar interbody fusion, particularly in osteoporotic conditions.

BACKGROUND CONTEXT: Early fusion is crucial in interbody procedures to minimize mechanical complications resulting from delayed union, especially for patients with osteoporosis. Bone morphogenetic proteins (BMPs) are used in spinal fusion procedures; however, limited evaluation exists regarding time-to-fusion for BMP use, particularly in patients with osteoporosis. PURPOSE: To evaluate the difference in time-to-fusion after single-level transforaminal lumbar interbody fusion (TLIF) surgery between recombinant human bone morphogenetic protein-2 (rhBMP-2) usage and nonusage groups according to bone density. STUDY DESIGN: Retrospective single-center cohort study. PATIENT SAMPLE: This study enrolled 132 patients (mean age, 65.25±8.66; male patients, 40.9%) who underwent single-level TLIF for degenerative disorders between February 2012 and December 2021, with pre and postoperative computed tomography (CT). OUTCOME MEASURE: The interbody fusion mass and bone graft status on postoperative CT scans was obtained annually, and time-to-fusion was recorded for each patient. METHODS: The patients were divided into 2 groups based on rhBMP-2 use during the interbody fusion procedure. Patients were further divided into osteoporosis, osteopenia, and normal groups based on preoperative L1 vertebral body attenuation values, using cutoffs of 90 and 120 Hounsfield units. It was strictly defined that fusion is considered complete when a trabecular bone bridge was formed, and therefore, the time-to-fusion was measured in years. Time-to-fusion was statistically compared between BMP group and non-BMP groups, followed by further comparison according to bone density. RESULTS: The time-to-fusion differed significantly between BMP and non-BMP groups, with half of the patients achieving fusion within 2.5 years in the BMP group compared with 4 years in the non-BMP group (p<.001). The fusion rate varied based on bone density, with the maximum difference observed in the osteoporosis group, when half of the patients achieved fusion within 3 years in the BMP group compared to 5 years in the non-BMP group (p<.001). Subgroup analysis was conducted, revealing no significant associations between time-to-fusion and factors known to influence the fusion process, including age, gender, medical history, smoking and alcohol use, and medication history, except for rh-BMP2 use and bone density. CONCLUSIONS: RhBMP-2 usage significantly reduced time-to-fusion in single-level TLIF, especially in patients with osteoporosis. LEVEL OF EVIDENCE: Level III.

Association of Untreated Pre-surgical Depression With Pain and Outcomes After Spinal Surgery.

STUDY DESIGN: Prospective Cohort Study. OBJECTIVE: Untreated pre-surgical depression may prolong post-surgical pain and hinder recovery. However, research on the impact of untreated pre-surgical depression on post-spinal surgery pain is lacking. Therefore, this study aimed to assess pre-surgical depression in patients and analyze its relationship with post-surgical pain and overall post-surgical outcomes. METHODS: We recruited 100 patients scheduled for lumbar spine surgery due to spondylolisthesis, degenerative lumbar disc diseases, and herniated lumbar disc diseases. Psychiatrists evaluated them for the final selection. We assessed the Beck Depression Inventory (BDI), Japanese Orthopaedic Association (JOA), Oswestry Disability Index (ODI), and EuroQoL 5 Dimensions (EQ-5D) scores, numerical back and leg pain scales, and medication dosage data collected before and at 6 weeks, 3 months, and 6 months after surgery. RESULTS: Ninety-one patients were included in this study; 40 and 51 were allocated to the control and depression groups, respectively. The pre- and post-surgical leg pain, back pain, and functional scores were not different. However, the depression group showed higher ODI and EQ-5D and lower JOA scores than the control group 3 months post-surgery. Partial correlation analysis revealed an inverse correlation between the JOA and BDI scores and a positive correlation between the EQ-5D and BDI scores at 3 months postoperatively. CONCLUSION: Untreated depression can prolong postoperative pain and hinder recovery. Detecting and treating depression in patients before spine surgery may improve their overall quality of life and functional recovery.

Analysis of factors that affect shoulder balance after correction surgery in scoliosis: a global analysis of all the curvature types.

PURPOSE: To identify factors that can affect postoperative shoulder balance in AIS. METHOD: 89 adolescent idiopathic scoliosis patients with six types of curvatures who underwent surgery were included in this study. Whole spine antero-posterior and lateral radiographs were obtained pre- and postoperatively. In radiograms, shape and changes in curvatures were analyzed. In addition, four shoulder parameters and coronal balance were analyzed in an effort to identify factors significantly related to postoperative shoulder balance. RESULT: In general, all the four shoulder parameters (CHD, CA, CRID, RSH) were slightly increased at final follow up (t test, P < 0.05), although there was a decrease in Lenke type II and IV curvatures. However, pre- and postoperative shoulder parameters were not significantly different between each curvature types (ANOVA, P > 0.05). Moreover, no significant differences of pre- and postoperative shoulder level between different level of proximal fusion groups (ANOVA, P > 0.05) existed. In the analysis of coronal curvature changes, no difference was observed in every individual coronal curvatures between improved shoulder balance and aggravated groups (P > 0.05). However, the middle to distal curve change ratio was significantly lower in patients with aggravated shoulder balance (P < 0.05). In addition, patients with smaller preoperative shoulder imbalance showed the higher chance of aggravation after surgery with similar postoperative changes (P < 0.05). CONCLUSIONS: Significant relations were found between correction rate of middle, and distal curvature, and postoperative shoulder balance. In addition, preoperative shoulder level difference can be a determinant of postoperative shoulder balance.

Effectiveness of Toothbrushing Technique for Biofilm Removal and Postoperative Infection Control after Spinal Fusion Surgery: A Retrospective Study.

This retrospective study was designed to investigate the effectiveness of using a toothbrush, which is commonly used in our daily life, for biofilm removal and infection control in the treatment of spinal infections occurring after spinal fusion surgery. Currently, a biofilm is thought to form on the surface of the metal inserted during spine fusion surgery. We aim to determine the differences in clinical outcomes between using and not using a toothbrush to remove biofilm while performing conventional drainage, curettage, and debridement. A total of 1081 patients who underwent anterior or posterior spinal fusion surgery between November 2018 and October 2022 were screened. The study included 60 patients who developed surgical site infection and underwent incision and drainage surgery either with a toothbrush (n = 20) or without a toothbrush (n = 40). Failure of infection control that requires revision surgery occurred in 2 patients (10%) in the Toothbrush group and in 14 patients (35%) in the No-Toothbrush group (p = 0.039). Thus, the rate of additional surgery was significantly lower in the Toothbrush group. Additionally, normalization of c-reactive protein levels occurred significantly faster in the Toothbrush group (p = 0.044). Therefore, using a toothbrush to treat spinal infections following spinal fusion surgery appears to have beneficial mechanical debridement effects, resulting in improved clinical results, which were also confirmed based on the electron microscopic images.

The Clinical Use of Osteobiologic and Metallic Biomaterials in Orthopedic Surgery: The Present and the Future.

As the area and range of surgical treatments in the orthopedic field have expanded, the development of biomaterials used for these treatments has also advanced. Biomaterials have osteobiologic properties, including osteogenicity, osteoconduction, and osteoinduction. Natural polymers, synthetic polymers, ceramics, and allograft-based substitutes can all be classified as biomaterials. Metallic implants are first-generation biomaterials that continue to be used and are constantly evolving. Metallic implants can be made from pure metals, such as cobalt, nickel, iron, or titanium, or from alloys, such as stainless steel, cobalt-based alloys, or titanium-based alloys. This review describes the fundamental characteristics of metals and biomaterials used in the orthopedic field and new developments in nanotechnology and 3D-printing technology. This overview discusses the biomaterials that clinicians commonly use. A complementary relationship between doctors and biomaterial scientists is likely to be necessary in the future.

A Comparative Analysis of Bi-Portal Endoscopic Spine Surgery and Unilateral Laminotomy for Bilateral Decompression in Multilevel Lumbar Stenosis Patients.

The clinical and radiological results before and after surgery were compared and analyzed for patients with multilevel lumbar stenosis who underwent bi-portal endoscopic spine surgery (BESS) and microscopic unilateral laminotomy for bilateral decompression (ULBD). We retrospectively identified 47 and 49 patients who underwent BESS and microscopic ULBD, respectively, who were diagnosed with multi-level lumbar stenosis. Clinical outcomes were evaluated using the visual analog scale score for both back and leg pain, and medication (pregabalin) use and Oswestry Disability Index (ODI) scores for overall treatment outcomes were used pre-operatively and at the final follow-up. Radiological outcomes were evaluated as the percentage of dura expansion volume, and percentage preservation of both facets and both lateral recess angles. The follow-up period of patients was about 17.04 months in the BESS group and about 16.90 months in the microscopic ULBD group. The back and leg visual analog scale (VAS) scores and average pregabalin use decreased more significantly in the BESS group than in the microscopic ULBD group (each p-value 0.0443, <0.001, 0.0378). All radiological outcomes were significantly higher in the BESS group than in the ULBD group. The change in ODI in two-level spinal stenosis showed a significantly higher value in the BESS group compared to the microscopic ULBD group (p-value 0.0335). Multilevel decompression with the BESS technique in multiple spinal stenosis is an adequate technique as it shows better clinical and radiological results than microscopic ULBD during a short-term follow-up period.