The Relationship between Perioperative Blood Transfusion and Postoperative Delirium in Patients Undergoing Spinal Fusion Surgery: Clinical Data Warehouse Analysis.

Background and Objectives: For preventing postoperative delirium (POD), identifying the risk factors is important. However, the relationship between blood transfusion and POD is still controversial. The aim of this study was to identify the risk factors of POD, to evaluate the impact of blood transfusion in developing POD among people undergoing spinal fusion surgery, and to show the effectiveness of big data analytics using a clinical data warehouse (CDW). Materials and Methods: The medical data of patients who underwent spinal fusion surgery were obtained from the CDW of the five hospitals of Hallym University Medical Center. Clinical features, laboratory findings, perioperative variables, and medication history were compared between patients without POD and with POD. Results: 234 of 3967 patients (5.9%) developed POD. In multivariate logistic regression analysis, the risk factors of POD were as follows: Parkinson's disease (OR 5.54, 95% CI 2.15-14.27; p < 0.001), intensive care unit (OR 3.45 95% CI 2.42-4.91; p < 0.001), anti-psychotics drug (OR 3.35 95% CI 1.91-5.89; p < 0.001), old age (≥70 years) (OR 3.08, 95% CI 2.14-4.43; p < 0.001), depression (OR 2.8 95% CI 1.27-6.2; p < 0.001). The intraoperative transfusion (OR 1.1, 95% CI 0.91-1.34; p = 0.582), and the postoperative transfusion (OR 0.91, 95% CI 0.74-1.12; p = 0.379) had no statistically significant effect on the incidence of POD. Conclusions: There was no relationship between perioperative blood transfusion and the incidence of POD in spinal fusion surgery. Big data analytics using a CDW could be helpful for the comprehensive understanding of the risk factors of POD, and for preventing POD in spinal fusion surgery.

Efficacy and radiographic analysis of oblique lumbar interbody fusion in treating lumbar degenerative spondylolisthesis with sagittal imbalance.

The aim of this study was to evaluate the effectiveness of OLIF (oblique lumbar interbody fusion) in the treatment of lumbar degenerative spondylolisthesis with sagittal imbalance. Fifty-nine patients were included in our analysis. Included patients were divided into 2 groups according to the surgical techniques: PLIF (posterior lumbar interbody fusion) (n = 31) and OLIF + PSF (OLIF combined with posterior spinal fixation) (n = 28). Perioperative radiographic parameters, complications, and clinical outcome from each group were assessed and compared. The operation time for both groups was 165.1 min in the OLIF group and 182.1 min in the PLIF group (P < 0.05). The intraoperative blood loss was 190.6 ml in the OLIF group and 356.3 ml in the PLIF group (P < 0.05). The number of intraoperative and postoperative complications for both groups was 7 in the OLIF group and 11 in the PLIF group. Significant clinical improvement was observed in VAS scores and ODI when comparing preoperative evaluation and final follow-up. The preoperative SVA (the distance from the posterosuperior corner of S1body to the C7 plumb line), PI (pelvic incidence), LL (lumbar lordosis), PI-LL mismatch, DH (disc height), and lumbar Cobb angles of both groups were similar. The postoperative and final follow-up SVA, LL, PI-LL mismatch, and disc height were improved in both groups, and a statistical difference was found between both groups (P < 0.05). An improvement of SVA, LL, PI-LL mismatch, and disc height at the OLIF group was better than that found at the PLIF group. An improvement in radiographic and clinical outcomes for the OLIF group was better than that seen for the PLIF group. Then, OLIF had a more curative effect in lumbar degenerative spondylolisthesis with sagittal imbalance.

Oblique retroperitoneal approach for lumbar interbody fusion from L1 to S1 in adult spinal deformity.

In recent years, with advancements in surgical techniques and instrumentation, the lateral lumbar interbody fusion is being used increasingly as an alternative procedure to anterior approach. In this study, we illustrated a oblique retroperitoneal approach for lumbar interbody fusion with one incision site and tilting of the operation table in adult spinal deformity and evaluate the radiographical findings and clinical outcomes of patients treated using this technique. This study included 32 patients scheduled to undergo anterior and posterior long-level fusions for lumbar degenerative kyphosis or degenerative lumbar scoliosis. Data collected included blood loss, operative time, incision size, and perioperative complications. Pre- and postoperative radiographic parameters and clinical outcome measures were assessed. Mean follow-up time was 26.1 months. The mean blood losses were 107.4 and 102.4 ml, and the mean operative times were 116, 97, and 82 min for the patients within five levels (4 cases), four levels (18 cases), and three levels (10 cases). The mean incision sizes were 14.63, 13.82, and 12.5 cm in the patients with five, four, and three levels. The mean pelvic incidence was 50.3°. The mean preoperative sagittal vertical axis (SVA) was + 13.66 cm, and the last follow-up SVA was + 2.94 cm. The preoperative lumbar lordosis (LL) was 5.79°, and the last follow-up LL was 46.54°. The mean correction angle was 41°. The mean Cobb angle decreased from a preoperative value of 21.55° to 9.6°at the last follow-up. An oblique retroperitoneal approach is very safe, allowing reproducible access from L1 to S1 for lumbar interbody fusion in adult spinal deformity.

Efficacy of Minimally Invasive Oblique Lumbar Interbody Fusion Using Polyetheretherketone Cages for Lumbar Pyogenic Spondylodiscitis Treatment.

(1) Background: This study evaluated the efficacy and safety of a minimally invasive oblique lumbar interbody fusion (OLIF) using polyetheretherketone (PEEK) cages for the treatment of lumbar pyogenic spondylodiscitis. (2) Methods: Fifty-one patients with single-level lumbar pyogenic spondylodiscitis were included in the study. Patients were divided into two groups: anterior lumbar interbody fusion with a tri-cortical iliac bone graft (ALIF+ tri-cortical iliac bone graft) (n = 28) and OLIF using PEEK cages with an autologous bone graft (OLIF+ PEEK cages) (n = 23). Perioperative radiographic parameters, complications, and clinical outcomes in both groups were analyzed and compared. (3) Results: The postoperative and final follow-up LL (lumbar lordosis) and RL (regional lordosis) were improved in both groups (p < 0.001). But, compared with the ALIF group, the OLIF group had more improvement of the RL. The operation time was 79 min for the OLIF group and 101 min for the ALIF group (p < 0.05). The intraoperative blood loss was 92 mL for the OLIF group and 114 mL for the ALIF group (p < 0.05). Significant clinical improvement was observed in visual analogue scale scores for the back and Oswestry Disability Index in both groups (p < 0.001). There was no recurrence of infection. (4) Conclusions: Compared with the ALIF group, the OLIF group had more improvement in radiographic and clinical outcomes. Thus, OLIF using PEEK cages with an autologous bone graft could be proposed for the surgical treatment of lumbar pyogenic spondylodiscitis.

The Impact of Blood Transfusion in Developing Postoperative Delirium in Patients with Hip Fracture Surgery.

BACKGROUND: Many studies have been conducted to explore the risk factors associated with postoperative delirium (POD) in order to understand its underlying causes and develop prevention strategies, especially for hip fracture surgery. However, the relationship between blood transfusion and POD has been heatedly debated. The purpose of this study was to evaluate the risk factors of POD and the relationship between blood transfusions and the occurrence of POD in hip fracture surgery through big data analysis. METHODS: Medical data (including medication history, clinical and laboratory findings, and perioperative variables) were acquired from the clinical data warehouse (CDW) of the five hospitals of Hallym University Medical Center and were compared between patients without POD and with POD. RESULTS: The occurrence of POD was 18.7% (228 of 2398 patients). The risk factors of POD included old age (OR 4.38, 95% CI 2.77-6.91; p < 0.001), American Society of Anesthesiology physical status > 2 (OR 1.84 95% CI 1.4-2.42; p < 0.001), dementia (OR 1.99, 95% CI 1.53-2.6; p < 0.001), steroid (OR 0.53 95% CI 0.34-0.82; p < 0.001), Antihistamine (OR 1.53 95% CI 1.19-1.96; p < 0.001), and postoperative erythrocyte sedimentation rate (mm/h) (OR 0.97 95% CI 0.97-0.98; p < 0.001) in multivariate logistic regression analysis. The postoperative transfusion (OR 2.53, 95% CI 1.88-3.41; p < 0.001) had a significant effect on the incidence of POD. CONCLUSIONS: big data analytics using a CDW was a good option to identify the risk factors of POD and to prevent POD in hip fracture surgery.

The influence of thoracic inlet alignment on the craniocervical sagittal balance in asymptomatic adults.

STUDY DESIGN: A prospective radiographic study. OBJECTIVES: To analyze the relationship between craniocervical sagittal balance and thoracic inlet (TI) alignment and to present the parameters that would help predict physiological lordosis of the cervical spine. SUMMARY OF BACKGROUND DATA: The physiological cervical lordosis (CL) and related factors has not been clearly defined yet. No studies have reported correlations between TI alignment and sagittal balance of the cervical spine. METHODS: Cervical spine lateral radiograph of 77 asymptomatic adult volunteers (aged between 21 and 50 y) were taken to analyze the following parameters. (1) Thoracic inlet parameters: thoracic inlet angle (TIA), T1 slope, neck tilting (NT); (2) cervical spine parameters: C0-2 angle, C2-7 angle, % ratio of (C0-2/C0-7 angle), (C2-7/C0-7 angle), and cervical tilting; (3) cranial parameters: C0 angle, cranial offset, and cranial tilting. Statistical analysis was performed using the Pearson correlation coefficients and multiple regression analysis. RESULTS: The mean TIA, T1 slope, NT were 69.5, 25.7, and 43.7, respectively. The mean C0-2 angle, C2-7 angle, C0 angle, cranial offset, cervical tilting, and cranial tilting were -22.4 degrees, -9.9 degrees, -9.3 degrees, 20.9 mm, 18 degrees, and 7.7 degrees, respectively. The ratio of C0-2:C2-7 angle was maintained as 77:23% and cervical tilting:cranial tilting was 70.2:29.8%. A significant correlation was found between TIA and T1 slope (r=0.694), T1 slope and C2-7 angle (r=-0.624), C2-7 angle and C0-2 angle (r=-0.547), C0-2 angle and cranial offset (r=-0.406). CONCLUSIONS: The thoracic inlet alignment had significant correlations with craniocervical sagittal balance. To preserve physiological NT around 44 degrees, large TIA increased T1 slope and CL and vice versa. TIA and T1 slope could be used as parameters to predict physiological alignment of the cervical spine. The results of this study may serve as baseline data for the evaluation of sagittal balance or planning of a fusion angle in the cervical spine.

Efficacy and Radiographic Analysis of Minimally Invasive Posterior Mono-Axial Pedicle Screw Fixation in Treating Thoracolumbar Burst Fractures.

BACKGROUND: The purpose of this study was to evaluate the effectiveness of minimally invasive posterior mono-axial pedicle screws fixation in the treatment of thoracolumbar burst fractures. METHODS: In the present study, we analyzed 98 patients retrospectively who had thoracolumbar burst fractures without a neurological deficit. Patients were divided into two groups: mono-axial pedicle screw fixation group (n = 52) and poly-axial pedicle screw fixation group (n = 46). We collected clinical data (visual analog scale (VAS) score for back pain) and included radiographic measurements. RESULTS: Sagittal index was significantly improved at postop and last follow-up in the mono group and the poly group. The mono group was better for reducing and maintaining anterior vertebral height. For the mono group, the mean postoperative regional kyphosis correction rate was 62.31%, and correction loss was 14.18% in late follow-up. For the poly group, the mean postoperative regional kyphosis correction rate was 52.17%, and correction loss was 33.42% in late follow-up. The mono-axial pedicle screw group had a good correction rate and reduced the risks of correction loss. The mean VAS scores for back pain improved by 2.4/2.5 and 3.8/4.2 for the mono and poly groups, respectively. There was no significant difference between groups. CONCLUSIONS: The mono-axial pedicle screw fixation was better for reducing and maintaining anterior vertebral height and regional kyphosis. Therefore, the mono-axial pedicle screw is a better optional instrumentation to treat thoracolumbar vertebral fractures.

Endoscopic Spinal Surgery (BESS and UESS) Versus Microscopic Surgery in Lumbar Spinal Stenosis: Systematic Review and Meta-Analysis.

STUDY DESIGN: Systematic Review and Meta-Analysis. OBJECTIVES: Various minimally invasive surgical techniques have been developed as alternatives to conventional surgery. According to recent studies, endoscopic spinal surgery (ESS) (biportal ESS [BESS] or uniportal ESS [UESS]) is more favorable compared with microscopic spinal surgery (MSS). This systematic review and meta-analysis aimed to assess the latest evidence on the use of ESS compared with MSS in lumbar spinal stenosis. METHODS: A systematic electronic search using PubMed, Embase, Cochrane Central Database, and Korea Med was performed until December 2019 to identify studies that compared ESS and MSS in patients with lumbar spinal stenosis. RESULTS: Overall, 1167 patients were included from three randomized controlled trials, six retrospective cohorts, and two prospective case-control studies. This review only presented 3 direct comparative studies. The study had inherent limitations specifically in terms of the study design. Meta-analysis of hospital stay (days) showed significant difference between BESS and MSS, UESS and MSS, BESS +UESS, and MSS at the final follow-up (95% confidence interval [CI]: -3.66 to -.77; P = .003; I2 = 97%, 95% CI: -2.95 to -1.22; P <.00001; I2 = 90%, and 95% CI: -2.89 to -1.48; P <.00001; I2 = 96%, respectively). However, meta-analysis showed no significant difference in other results. CONCLUSIONS: Although a shorter duration of hospital stay was observed in ESS, there were no significant differences in efficacy and safety between ESS and MSS. Further studies are required to validate these results.

The Influence of High Blood Pressure on Developing Symptomatic Lumbar Epidural Hematoma after Posterior Lumbar Spinal Fusion Surgery: Clinical Data Warehouse Analysis.

BACKGROUND: Determining the risk factors for symptomatic lumbar epidural hematoma (SLEH) is important for preventing postoperative SLEH. However, the relationship between blood pressure and SLEH is still debatable. The purpose of our study was to determine the risk factors for postoperative SLEH, to assess the influence of high blood pressure on developing SLEH after posterior lumbar spinal fusion surgery, and to evaluate the usefulness of big data analysis utilizing a clinical data warehouse (CDW). METHODS: The clinical data of patients who had undergone posterior lumbar spinal fusion surgery were acquired from the CDW of Hallym University Medical Center. The acquired clinical data were compared between patients without postoperative SLEH and with postoperative SLEH. RESULTS: Postoperative SLEH that required hematoma evacuation surgery within 72 h after posterior lumbar spinal fusion surgery occurred in 17 (1.3%) of 1313 patients. According to the multivariate logistic regression analysis, the risk factors for postoperative SLEH are platelet count difference (OR 1.28, p = 0.03), postoperative international normalized ratio (INR) difference (OR 31.4, p = 0.028), and postoperative systolic blood pressure (SBP) difference (≥10 mmHg) (OR 1.68, p = 0.048). An increase in postoperative SBP (OR 1.68, p = 0.048) had a statistically significant influence on the occurrence of postoperative SLEH. CONCLUSIONS: Big data analysis utilizing a CDW could be useful for extending our knowledge of the risk factors for postoperative SLEH and preventing postoperative SLEH after posterior lumbar spinal fusion surgery.

B.1.1.7 (Alpha) variant is the most antigenic compared to Wuhan strain, B.1.351, B.1.1.28/triple mutant and B.1.429 variants.

The rapid spread of the SARS-CoV-2 virus and its variants has created a catastrophic impact worldwide. Several variants have emerged, including B.1.351 (Beta), B.1.1.28/triple mutant (P.1), B.1.1.7 (Alpha), and B.1.429 (Epsilon). We performed comparative and comprehensive antigenicity mapping of the total S-glycoprotein using the Wuhan strain and the other variants and identified 9-mer, 15-mer, and 20-mer CTL epitopes through in silico analysis. The study found that 9-mer CTL epitope regions in the B.1.1.7 variant had the highest antigenicity and an average of the three epitope types. Cluster analysis of the 9-mer CTL epitopes depicted one significant cluster at the 70% level with two nodes (KGFNCYFPL and EGFNCYFPL). The phage-displayed peptides showed mimic 9-mer CTL epitopes with three clusters. CD spectra analysis showed the same band pattern of S-glycoprotein of Wuhan strain and all variants other than B.1.429. The developed 3D model of the superantigen (SAg)-like regions found an interaction pattern with the human TCR, indicating that the SAg-like component might interact with the TCR beta chain. The present study identified another partial SAg-like region (ANQFNSAIGKI) from the S-glycoprotein. Future research should examine the molecular mechanism of antigen processing for CD8+ T cells, especially all the variants' antigens of S-glycoprotein.

Sodium Selenite Promotes Osteoblast Differentiation via The WNT/ß-Catenin Signaling Pathway.

Objective: Osteoporosis is regarded as a silent disorder affecting bone slowly, leading to an increased risk of fractures. Lately, selenium has been found to be associated with the acquisition and maintenance of bone health by affecting the bone remodeling process. However, the mechanism of action of selenium on bone is poorly understood. Here, the objective of this study is to examine the protective effects and mechanism of sodium selenite on the differentiation process of osteoblasts as well as under oxidative stress-induced conditions by evaluating the expression of osteoblast differentiation markers in the sodium selenite and/or hydrogen peroxide (H2O2)-treated MC3T3-E1 cell line. Materials and Methods: In this experimental study, we confirmed the inducible osteogenic effect of sodium selenite on MC3T3-E1 cells. Moreover, we investigated the recovery of expression levels of osteogenic markers of sodium selenite in (H2O2)-treated MC3T3-E1 cells. Results: It was observed that sodium selenite could promote alkaline phosphatase (ALP) activity and collagen synthesis in pre-osteoblasts. Also, sodium selenite enhanced the mRNA expression levels of osteogenic transcriptional factors, like osterix (OSX) and runt-related transcription factor 2 (Runx2). In addition, the terminal differentiation markers, such as osteocalcin (OCN) and collagen 1α (Col1α) were also increased after the treatment of sodium selenite. Also treatment of sodium selenite recused the (H2O2)-induced inhibition of osteoblastic differentiation of pre-osteoblasts cells via the WNT signaling pathway, implicating its antioxidant activity. Furthermore, sodium selenite restored the (H2O2) repressed ß-catenin stability and axin-2 reporter activity in MC3T3-E1 cells. Conclusion: It may be concluded that sodium selenite can stimulate bone formation and rescue the oxidative repression of osteogenesis by activating WNT signaling pathways. Further detailed studies on the role of selenium and its ability to stimulate bone formation via the WNT signaling pathway may project it as a potential therapeutic intervention for osteoporosis.

Efficacy and radiographic analysis of oblique lumbar interbody fusion in treating adult spinal deformity.

Adult spinal deformity (ASD) is usually rigid and requires a combined anterior-posterior approach for deformity correction. Anterior lumbar interbody fusion (ALIF) allows direct access to the disc space and placement of a large interbody graft. A larger interbody graft facilitates correction of ASD. However, an anterior approach carries significant risks. Lateral lumbar interbody fusion (LLIF) through a minimally invasive approach has recently been used for ASD. The present study was performed to evaluate the effectiveness of oblique lumbar interbody fusion (OLIF) in the treatment of ASD. We performed a retrospective study utilizing the data of 74 patients with ASD. The inclusion criteria were lumbar coronal Cobb angle > 20°, pelvic incidence (PI)-lumbar lordosis (LL) mismatch > 10°, and minimum follow-up of 2 years. Patients were divided into two groups: ALIF combined with posterior spinal fixation (ALIF+PSF) (n = 38) and OLIF combined with posterior spinal fixation (OLIF+PSF) (n = 36). The perioperative spinal deformity radiographic parameters, complications, and health-related quality of life (HRQoL) outcomes were assessed and compared between the two groups. The preoperative sagittal vertical axis (SVA), LL, PI-LL mismatch, and lumbar Cobb angles were similar between the two groups. Patients in the OLIF+PSF group had a slightly higher mean number of interbody fusion levels than those in the ALIF+PSF group. At the final follow-up, all radiographic parameters and HRQoL scores were similar between the two groups. However, the rates of perioperative complications were higher in the ALIF+PSF than OLIF+PSF group. The ALIF+PSF and OLIF+PSF groups showed similar radiographic and HRQoL outcomes. These observations suggest that OLIF is a safe and reliable surgical treatment option for ASD.

Comparison of the effectiveness of extensor muscle strengthening exercise by itself, exercise with polydeoxyribonucleotide injection, and exercise with extracorporeal shockwave therapy in lateral epicondylitis: a randomized controlled trial.

BACKGROUND: Extensor muscle strengthening exercises with counterforce braces (EX) is a conventional conservative treatment for lateral epicondylitis (LE) of the elbow. In addition, polydeoxyribonucleotide (PDRN) or extracorporeal shockwave therapy (ESWT) has been recently used for LE. METHODS: Sixty-three patients with chronic LE participated in this study and randomly allocated in three groups (G1: EX, G2: EX+PDRN injection, and G3: EX+ESWT). All of the three groups were taught to perform EX at the first out-patient department (OPD) visit. Group 2 was injected with 3 mL PDRN (5.625 mg/3 mL), while group 3 received ESWT at the first OPD visit. Visual analog scale pain score, Mayo elbow performance score (MEPS), and ultrasonographic examination were checked before, 6 weeks, and 12 weeks after the treatments. RESULTS: Overall functional scores and ultrasonographic findings in all three groups improved after treatment. The mean MEPS in group 2 improved more than groups 1 and 3 at 6 weeks (G1, 56.9>62.4; G2, 54.3>65.0; G3, 55.7>62.6), and more than group 1 at 12 weeks (G1, 56.9>67.9; G2, 54.3>73.6). The mean common extensor tendon depth (CETD) on ultrasonography in group 2 increased more than groups 1 and 3 at 6 and 12 weeks (6 weeks: G1, 0.385>0.386; G2, 0.332>0.392; G3, 0.334>0.357; 12 weeks: G1, 0.385>0.409; G2, 0.332>0.438; G3, 0.334>0.405 [cm]). CONCLUSIONS: PDRN injections combined with EX exhibited a greater improvement in mean MEPS and mean CETD compared to EX only or EX combined with ESWT for LE within the 12 weeks follow-up.

Single-Stage Posterior Subtotal Corpectomy and Circumferential Reconstruction for the Treatment of Unstable Thoracolumbar Burst Fractures.

OBJECTIVE: To illustrate the technique of single-stage posterior subtotal corpectomy and circumferential reconstruction for the treatment of unstable thoracolumbar burst fractures and to evaluate the radiographical and clinical outcomes of patients treated using this technique. METHODS: 16 consecutive patients with unstable thoracolumbar burst fractures were treated with single-stage posterior subtotal corpectomy and circumferential reconstruction. The mean patient age was 54.8 years. The mean follower up period was 25 months. Five patients suffered from T12 fractures, 10 from L1, 1 from L2. The segmental kyphosis, neurologic status, visual analogue scale for back pain was evaluated before surgery and at follow up. RESULTS: The segmental kyphotic angle improved from 18.5 degrees before surgery to -9.2 degrees at the last follow up. The mean correction angle was 28.9 degrees. The mean surgical time was 255 minutes, and a mean intraoperative blood loss was 1073 mL. Intraoperative complications included two dural tears, and a superficial wound infection. There were no other severe complications. The mean visual analog scale of back pain decreased from a mean value of 6.6 to 2 at the last follow up. CONCLUSION: The single-stage posterior subtotal corpectomy and circumferential reconstruction achieved satisfactory kyphosis correction with direct visualization of the circumferentially decompressed spinal cord, as well as good fusion with less blood loss and complications. It is a safe and reliable surgical treatment option for unstable thoracolumbar burst fractures.

DNA barcoding to fishes: current status and future directions.

DNA barcoding appears to be a promising approach for taxonomic identification, characterization, and discovery of newer species, facilitating biodiversity studies. It helps researchers to appreciate genetic and evolutionary associations by collection of molecular, morphological, and distributional data. Fish DNA barcoding, based on the sequencing of a uniform area of Cytochrome C Oxidase type I (COI) gene, has received significant interest as an accurate tool for species identification, authentication, and phylogenetic analysis. The aim of this review article was to investigate recent global status, approaches, and future direction of DNA barcoding in fisheries sectors. We have tried to highlight its possible impacts, complications, and validation issues at species levels for biodiversity analysis. Moreover, an effort has been put forward to understand issues related to various marker genes associated with barcode process as primer sequences and have concluded barcode promotion as an indispensable tool of molecular biology for the development of taxonomic support systems.

Genetic polymorphism in extracellular regulators of Wnt signaling pathway.

The Wnt signaling pathway is mediated by a family of secreted glycoproteins through canonical and noncanonical mechanism. The signaling pathways are regulated by various modulators, which are classified into two classes on the basis of their interaction with either Wnt or its receptors. Secreted frizzled-related proteins (sFRPs) are the member of class that binds to Wnt protein and antagonizes Wnt signaling pathway. The other class consists of Dickkopf (DKK) proteins family that binds to Wnt receptor complex. The present review discusses the disease related association of various polymorphisms in Wnt signaling modulators. Furthermore, this review also highlights that some of the sFRPs and DKKs are unable to act as an antagonist for Wnt signaling pathway and thus their function needs to be explored more extensively.

Factors determining cervical spine sagittal balance in asymptomatic adults: correlation with spinopelvic balance and thoracic inlet alignment.

BACKGROUND CONTEXT: Based on the previous studies, cervical lordosis (CL) is a parameter influenced by thoracic kyphosis (TK); however, the correlations still remain unclear. Few studies have analyzed the correlations between the cervical spine lordosis and global spinopelvic balance. To date, there has been no study focused on the factors determining cervical spine sagittal balance. PATIENT SAMPLE: Seventy-seven asymptomatic volunteers without the history of symptoms related to whole spine. OUTCOME MEASURES: Statistical significance of correlations of radiographic parameters on cervical spine and whole-spine standing lateral radiograph. PURPOSE: To analyze the factors determining cervical spine sagittal balance, including global spinopelvic balance and thoracic inlet (TI) alignment in asymptomatic adults. STUDY DESIGN: A prospective radiographic study. METHODS: Cervical and whole-spine standing lateral radiographs were taken to analyze the following parameters: spinopelvic parameters pelvic incidence (PI), sacral slope (SS), lumbar lordosis (LL), and TK; TI parameters thoracic inlet angle (TIA) and T1 slope; and cervical spine parameters C0-C2, C2-C7, and C0-C7 angles and cervical tilting. Statistical analysis was performed using the Pearson correlation coefficients and multiple regression analysis. RESULTS: All the parameters showed a normal distribution. There was a significant sequential linkage between PI and SS (r=0.653), SS and LL (r=0.807), LL and TK (r=-0.516), and TK and C0-C7 angle (r=-0.322). There was a significant relationship between TK and T1 slope (r=0.351) but no significant relationship between TK and TIA. There were significant sequential relationships between TIA and T1 slope (r=0.694), T1 slope and C2-C7 angle (r=-0.624), and C2-C7 and C0-C2 angles (r=-0.547). T1 slope was the only parameter that demonstrated a significant correlation with both SP and TI parameters. A linear regression model showed that T1 slope had a stronger relationship with TIA (r=0.694) than TK (r=0.351). CONCLUSIONS: T1 slope was a key factor determining cervical spine sagittal balance. Both spinopelvic balance and TI alignment have a significant influence on cervical spine sagittal balance via T1 slope, but TIA had a stronger effect than TK. An individual with large T1 slope required large CL to preserve physiologic sagittal balance of the cervical spine. The results of the present study could serve as baseline data for further studies on the cervical spine sagittal balance in various clinical conditions including the surgical reconstruction of lordosis.

Clinical and radiological outcomes of modified posterior closing wedge osteotomy for the treatment of posttraumatic thoracolumbar kyphosis.

OBJECT: Most thoracolumbar fractures have a good healing outcome with adequate treatment. However, posttraumatic thoracolumbar kyphosis can occur in a proportion of thoracolumbar fractures after inappropriate treatment, osteoporosis, or osteonecrosis of the vertebral body. There are several surgical options to correct posttraumatic thoracolumbar kyphosis, including anterior, posterior, and combined approaches, which are associated with varying degrees of success. The aim of this study was to assess the use of a modified closing wedge osteotomy for the treatment of posttraumatic thoracolumbar kyphosis and to evaluate the radiographic findings and clinical outcomes of patients treated using this technique. METHODS: Thirteen consecutive patients with symptomatic posttraumatic thoracolumbar kyphosis were treated using a modified closing wedge osteotomy. The mean patient age was 62 years. The kyphosis apex ranged from T-10 to L-2. The sagittal alignment, kyphotic angle, neurological function, visual analog scale for back pain, and Oswestry Disability Index were evaluated before surgery and at follow-up. RESULTS The mean preoperative regional angle was 27.4°, and the mean correction angle was 29.6°. Sagittal alignment improved with a mean correction rate of 58.3%. The mean surgical time was 275 minutes, and the mean intraoperative blood loss was 1585 ml. The intraoperative complications included 2 dural tears, 1 nerve root injury, and 1 superficial wound infection. The mean visual analog scale score for back pain improved from 6. 6 to 2, and the Oswestry Disability Index score decreased from 55.4 to 22.6 at the last follow-up. All patients achieved bony anterior fusion based on the presence of trabecular bone bridging at the osteotomy site. CONCLUTIONS: The modified posterior closing wedge osteotomy technique achieves satisfactory kyphosis correction with direct visualization of the circumferentially decompressed spinal cord, as well as good fusion with less blood loss and fewer complications. It is an alternative method for treating patients with posttraumatic thoracolumbar kyphosis.

The Incidence and Management of Dural Tears and Cerebrospinal Fluid Leakage during Corrective Osteotomy for Ankylosing Spondylitis with Kyphotic Deformity.

OBJECTIVE: To present the incidence and management of dural tears and cerebrospinal fluid leakage during corrective osteotomy [Pedicle Subtraction Osteotomy (PSO) or Smith-Petersen Osteotomy (SPO)] for ankylosing spondylitis with kyphotic deformity. METHODS: A retrospective study was performed for ankylosing spondylitis patients with fixed sagittal imbalance, who had undergone corrective osteotomy (PSO or SPO) at lumbar level. 87 patients were included in this study. 55 patients underwent PSO, 32 patients underwent SPO. The mean age of the patients at the time of surgery was 41.7 years (21-70 years). Of the 87 patients, 15 patients had intraoperative dural tears. RESULTS: The overall incidence of dural tears was 17.2%. The incidence of dural tears during PSO was 20.0%, SPO was 12.5%. There was significant difference in the incidence of dural tears based on surgical procedures (PSO vs. SPO) (p<0.05). The dural tears ranged in size from 12 to 221 mm(2). A nine of 15 patients had the relatively small dural tears, underwent direct repair via watertight closure. The remaining 6 patients had the large dural tears, consequently direct repair was impossible. The large dural tears were repaired with an on-lay graft of muscle, fascia or fat harvested from the adjacent operation site. All patients had a successful repair with no patient requiring reoperation for the cerebrospinal fluid leak. CONCLUSION: The overall incidence of dural tears during PSO or SPO for ankylosing spondylitis with kyphotic deformity was 17.2%. The risk factor of dural tears was complexity of surgery. All dural tears were repaired primarily using direct suture, muscle, fascia or fat graft.

Tribological changes in the articular cartilage of a human femoral head with avascular necrosis.

The present study evaluated the tribological properties of the articular cartilage surface of the human femoral head with postcollapse stage avascular necrosis (AVN) using atomic force microscopy. The cartilage surface in the postcollapse stage AVN of the femoral head was reported to resemble those of disuse conditions, which suggests that the damage could be reversible and offers the possibilities of success of head-sparing surgeries. By comparing the tribological properties of articular cartilage in AVN with that of osteoarthritis, the authors intended to understand the cartilage degeneration mechanism and reversibility of AVN. Human femoral heads with AVN were explanted from the hip replacement surgery of four patients (60-83 years old). Nine cylindrical cartilage samples (diameter, 5 mm and height, 0.5 mm) were sectioned from the weight-bearing areas of the femoral head with AVN, and the cartilage surface was classified according to the Outerbridge Classification System (AVN0, normal; AVN1, softening and swelling; and AVN2, partial thickness defect and fissuring). Tribological properties including surface roughness and frictional coefficients and histochemistry including Safranin O and lubricin staining were compared among the three groups. The mean surface roughness Rq values of AVN cartilage increased significantly with increasing Outerbridge stages: Rq = 137 ± 26 nm in AVN0, Rq = 274 ± 49 nm in AVN1, and Rq = 452 ± 77 nm in AVN2. Significant differences in Rq were observed among different Outerbridge stages in all cases (p < 0.0001). The frictional coefficients (µ) also increased with increasing Outerbridge stages. The frictional coefficient values were µ = 0.115 ± 0.034 in AVN0, µ = 0.143 ± 0.025 in AVN1, and µ = 0.171 ± 0.039 in AVN2. Similarly to the statistical analysis of surface roughness, significant statistical differences were detected between different Outerbridge stages in all cases (p < 0.05). Both surface roughness and frictional coefficient of cartilage, which were linearly correlated, increased with increasing Outerbridge stages in postcollapse AVN. The underlying mechanism of these results can be related to proteoglycan loss within the articular cartilage that is also observed in osteoarthritis. With regard to the tribological properties, the cartilage degeneration mechanism in AVN was similar to that of osteoarthritis without reversibility.