Efficacy of a 1 day Rifaximin and Metronidazole Regimen and Mechanical Bowel Preparation for Preventing Surgical Site Infection in Minimally Invasive Colorectal Cancer Surgery: A Prospective Observational Study.

BACKGROUND: A combination of oral antibiotics and mechanical bowel preparation is recommended for patients scheduled to undergo elective colorectal surgery on the basis of recent large trials that have reported the superiority of this approach in preventing surgical site infections (SSIs). However, there are no standard recommendations for this approach. Therefore, in this study, we evaluated the efficacy of rifaximin and metronidazole and mechanical bowel preparation for preventing SSIs in cases of minimally invasive surgery for colorectal cancer. METHODS: This single-arm prospective observational study included 256 individuals. The primary end point was the rate of SSI. Rifaximin 400 mg and metronidazole 500 mg were administered twice daily (10 am and 10 pm), and mechanical bowel preparation was administered the day before the operation. RESULTS: After excluding 15 patients, 241 were enrolled. No adverse event occurred following the administration of oral antibiotics and mechanical bowel preparation; there was 100% compliance. The total SSI rate was 2.9%; the rates of incisional and organ/space SSIs were 1.2% and 1.7%, respectively. All patients were treated conservatively. Univariate analyses revealed preoperative anemia, hypoalbuminemia, and transfusion and postoperative transfusion were significantly associated with SSIs. DISCUSSION: A 1 day rifaximin and metronidazole regimen with mechanical bowel preparation for elective minimally invasive surgery for colorectal cancer was associated with a favorable SSI rate of 2.9%, safety, and high compliance. This approach is appropriate for inclusion in the current guidelines for perioperative management of patients scheduled to undergo minimally invasive surgery for colorectal cancer.

Prognosis of spread through air spaces in invasive mucinous lung adenocarcinoma after curative surgery.

INTRODUCTION: The purpose of this study is to investigate the prognostic impact of spread through air spaces (STAS) in invasive mucinous adenocarcinoma (IMA). MATERIALS AND METHODS: From 2015 to 2019, patients who underwent complete resection of IMA were extracted from the prospective database. Multivariable Cox-regression analysis and inverse probability of treatment weight (IPTW) - adjusted log-rank test for 5-year recurrence-free survival (RFS) were performed. RESULTS: STAS was observed in 39.1% (53 out of 133). The STAS (+) group shows larger tumor size (2.9 ± 2.4 cm vs 3.8 ± 2.4 cm, p = 0.031) and higher incidence of lympho-vascular invasion (6 [7.5%] vs 18 [34.0%], p < 00.001) compared to the STAS (-) group. The 5-year RFS was 66.1% in the STAS (+) group and 91.8% in the STAS (-) group (p < 00.001), and the incidence of locoregional recurrence was significantly higher in the STAS (+) group than the STAS (-) group (1 [1.2%] vs 12 [22.6%], p < 00.001). Multivariable analysis revealed that STAS was associated with poor prognosis for all-recurrence (hazard ratio 2.81, 95% confidence interval 1.01-7.81, p = 0.048). After IPTW adjustment, 5-year RFS was 66.3% in the STAS (+) group and 92.9% in the STAS (-) group (p = 0.007), and risk for locoregional recurrence was greater in the STAS (+) group than the STAS (-) group (1.1 [0.9%] vs 20.8 [16.6%], p < 00.001). CONCLUSIONS: STAS showed negative prognostic impact on all-recurrence, especially due to locoregional recurrence, after curative resection of IMA.

Surgical outcomes of thoracoscopic thymectomy via the single-port subxiphoid approach versus the unilateral intercostal approach.

OBJECTIVES: The purpose of this study was to explore the safety and feasibility of video-assisted thoracic surgery (VATS) total thymectomy via the single-port subxiphoid approach compared with the intercostal approach. METHODS: From January 2018 to May 2022, patients who underwent VATS total thymectomy via the subxiphoid or unilateral intercostal approach and diagnosed with Masaoka-Koga stage I-II, non-myasthenic thymoma were included in this study. Perioperative outcomes, immediate and long-term pain evaluations were compared in a propensity score-matching analysis. RESULTS: In total, 95 patients were included and underwent the subxiphoid approach (n = 37) and the intercostal approach (n = 58). Propensity score yielded 2 well-matched cohorts of 30 patients and there was no significant demographical imbalance between the 2 groups. Compared with the intercostal approach, the subxiphoid group demonstrated favourable perioperative outcomes including the intraoperative blood loss (P = 0.025) and the median duration of hospital stay (P = 0.083). The immediate and long-term pain evaluations revealed that the subxiphoid group reported lower visual analogue scales at postoperative 24 h and lower total doses of fentanyl bolus infusions during hospitalization (P = 0.004 and 0.018, respectively), along with lower long-term neuropathic pain scale scores (P = 0.005) than patients in the intercostal group. CONCLUSIONS: VATS thymectomy via the single-port subxiphoid approach showed favourable perioperative outcomes compared to the intercostal approach. Moreover, the subxiphoid approach seemed both to cause minimal immediate postoperative pain and to have advantages in reducing long-term neuropathic pain compared with the intercostal approach.

The Optimal Treatment Strategy for Postoperative Anastomotic Leakage After Esophagectomy: a Comparative Analysis Between Endoscopic Vacuum Therapy and Conventional Treatment.

BACKGROUND: We compared the clinical outcomes between endoscopic vacuum therapy (EVT) and conventional treatment (CT) for the management of post-esophagectomy anastomotic leakage. METHODS: A retrospective review of the medical records of patients who underwent esophagectomy with esophagogastrostomy from November 2003 to August 2021 was conducted. Thirty-four patients who developed anastomotic leakage were analyzed according to whether they underwent CT (n = 13) or EVT (n = 21). RESULTS: The median time to complete healing was significantly shorter in the EVT group than in the CT group (16 [4-142] days vs. 70 [8-604] days; p = 0.011). The rate of clinical success was higher in the EVT group (90.5%) than in the CT group (66.7%, p = 0.159). A subgroup analysis showed more favorable outcomes for EVT in patients with thoracic leakage, including a higher clinical success rate (p = 0.037), more rapid complete healing (p = 0.004), and shorter hospital stays (p = 0.006). However, the results were not significantly different in patients with cervical leakage. Anastomotic strictures occurred in 3 EVT patients (14.3%) and 5 CT patients (50.0%) (p = 0.044), and the EVT group showed a trend towards improved freedom from anastomotic strictures (p = 0.105). CONCLUSIONS: EVT could be considered as an adequate treatment option for post-esophagectomy anastomotic leakage. EVT might have better clinical outcomes compared to CT for managing anastomotic leakage after transthoracic esophagogastrostomy, and further studies are needed to evaluate the effectiveness of EVT in patients who undergo cervical esophagogastrostomy.

Feasibility of using the homologous parietal peritoneum as a vascular substitute for venous reconstruction during abdominal surgery: An animal model.

BACKGROUND: The interest in vascular substitutes has recently increased. We evaluated the feasibility of using a homologous parietal peritoneum as a vascular substitute for venous reconstruction during abdominal surgery. METHODS: The inferior vena cava was replaced with a homologous parietal peritoneum after cross-linking with glutaraldehyde in 36 rabbits. At 7, 14, and 28 days, the patency rate, outer and inner graft diameters, histology, and immunohistochemistry were evaluated. RESULTS: Both the 7- and 14-day groups maintained vascular patency. Vascular patency was maintained in 3 rabbits in the 28-day group. The inner diameters of the anastomotic sites were 6.23 ± 0.18, 5.64 ± 0.16, and 2.34 ± 0.21 mm in the 7-day, 14-day, and 28-day groups, respectively. The midpoint inner diameters of the homologous parietal peritoneum grafts were 624 ± 0.46, 5.74 ± 0.26, and 2.14 ± 0.28 mm in each group, respectively. Endothelial cell proliferation on the homologous parietal peritoneum graft surfaces in all groups was based on the histological findings from the first group. Multiple neovascularizations of the homologous parietal peritoneum graft were found in the 14- and 28-day groups, indicating neo-media formation. Acute inflammation appeared to progress to the entire layer of the homologous parietal peritoneum graft without an intraluminal thrombus, but the graft was patent in the 14-day group. In the 28-day group, 6 rabbits showed near-total occlusion and a thrombus formed in the homologous parietal peritoneum graft at the anastomosis site with severe stricture; however, the rabbits were alive and had collateral vessel formation. CONCLUSION: Using homologous parietal peritoneum is feasible for venous reconstruction in abdominal surgery.

A Prospective, Multi-Center, Double-Blind, Randomized Study to Evaluate the Efficacy and Safety of the Synthetic Bone Graft Material DBM Gel with rhBMP-2 versus DBM Gel Used during the TLIF Procedure in Patients with Lumbar Disc Disease.

OBJECTIVE: This study is to evaluate the efficacy and safety of demineralized bone matrix (DBM) gel versus DBM gel with recombinant human bone morphogenetic protein-2 (rhBMP-2) used in transforaminal lumbar interbody fusion (TLIF). METHODS: This study was designed as a prospective, multi-center, double-blind method, randomized study. All randomized subjects underwent TLIF with DBM gel with rhBMP-2 group (40 patients) as an experimental group or DBM gel group (36 patients) as a control group. Post-operative observations were performed at 12, 24, and 48 weeks. The spinal fusion rate on computed tomography scans and X-rays films, Visual analog scale pain scores, Oswestry disability index and SF-36 quality of life (QOL) scores were used for the efficacy evaluation. The incidence rate of adverse device effects (ADEs) and serious adverse device effects (SADEs) were used for safety evaluation. RESULTS: The spinal fusion rate at 12 weeks for the DBM gel with rhBMP-2 group was higher with 73.68% compared to 58.82% for the DBM gel group. The 24 and 48 weeks were 72.22% and 82.86% for the DBM gel with rhBMP-2 group and 78.79% and 78.13%, respectively, for the DBM gel group. However, there were no significant differences between two groups in the spinal fusion rate at 12, 24, and 48 weeks post-treatment (p=0.1817, p=0.5272, p=0.6247). There was no significant difference between the two groups in the incidence rate of ADEs (p=0.3836). For ADEs in the experimental group, 'Pyrexia' (5.00%) was the most common ADE, followed by 'Hypesthesia', 'Paresthesia', 'Transient peripheral paralysis', 'Spondylitis' and 'Insomnia' (2.50%, respectively). ADEs reported in control group included 'Pyrexia', 'Chest discomfort', 'Pain', 'Osteoarthritis', 'Nephropathy toxic', 'Neurogenic bladder', 'Liver function analyses' and 'Urticaria' (2.86%, respectively). There was no significant difference between the two groups in the incidence rate of SADEs (p=0.6594). For SADE in the experimental group, ''Pyrexia' and 'Spondylitis' were 2.50%. SADE reported in the control group included 'Chest discomfort', 'Osteoarthritis' and 'Neurogenic bladder'. All SADEs described above were resolved after medical treatment. CONCLUSION: This study demonstrated that the spinal fusion rates of DBM gel group and DBM gel with rhBMP-2 group were not significantly different. But, this study provides knowledge regarding the earlier postoperative effect of rhBMP-2 containing DBM gel and also supports the idea that the longer term follow-up results are essential to confirm the safety and effectiveness.

Influence of Osteoporosis Following Spine Surgery on Reoperation, Readmission, and Economic Costs: An 8-Year Nationwide Population-Based Study in Korea.

OBJECTIVE: To evaluate the relationship between prevalence of osteoporosis and risk factors, medical costs, reoperation, and readmission in patients after spine surgery. METHODS: Patients >50 years old with thoracic or lumbar spine diseases who underwent spine surgery between 2005 and 2008 were selected from the Korean National Health Insurance Service databases for analysis. There were 147,676 patients selected, who were divided into 2 groups (osteoporosis and non-osteoporosis) and followed for 8 years. Multiple logistic regressions were performed to examine the effect of osteoporosis following spine surgery. RESULTS: Patients with osteoporosis showed significant increases in readmission rates (odds ratio = 1.26, P < 0.001). Osteoporosis was found to be significantly associated with longer hospital stays and increased medical costs regardless of the cause of spine disease. For readmission, there was a 62-day difference in hospitalization time and U.S. dollars $2040 difference in medical costs between the osteoporosis group and non-osteoporosis group. Total medical costs of the osteoporosis group were about U.S. dollars $310 million more than total medical costs of the non-osteoporosis group. Osteoporosis increased the risk of reoperation in fusion surgery, particularly in the first 3 months postoperatively (odds ratio = 1.34, P < 0.001). CONCLUSIONS: Osteoporosis was significantly associated with higher readmission rates, longer hospitalization, and greater medical costs during the 8-year follow-up. It also increased the risk of reoperation in fusion surgery. Proper management of osteoporosis is essential before spine surgery, particularly fusion surgery, to help reduce patients' socioeconomic burden and produce more satisfactory surgical outcomes.

Clinical, Radiographic, and Genetic Analyses in a Population-Based Cohort of Adult Spinal Deformity in the Older Population.

OBJECTIVE: This study aimed to identify the sagittal parameters associated with health-related quality of life and genetic variations that increase the risk of adult spinal deformity (ASD) onset in the older population. METHODS: We recruited 120 participants who had a sagittal vertical axis > 50 mm in a sagittal imbalance study. Sagittal radiographic parameters, cross-sectional area, and intramuscular fatty infiltration using the Goutallier classification in the paraspinal lumbar muscles were evaluated. Functional scales included the self-reported Oswestry Disability Index (ODI), 36-item Short Form Health Survey (SF-36), and visual analogue scales (VAS) for back and leg pain. We performed whole-exome sequencing and an exome-wide association study using the 100 control subjects and 63 individuals with severe phenotypes of sagittal imbalance. RESULTS: Pelvic incidence minus lumbar lordosis (PI-LL) mismatch was negatively associated with the SF-36 and positively correlated with ODI and VAS for back and leg pain. PI-LL was related to the quality and size of the paraspinal muscles, especially the multifidus muscle. We identified common individual variants that reached exome-wide significance using single-variant analysis. The most significant single-nucleotide polymorphism was rs78773460, situated in an exon of the SVIL gene (odds ratio, 9.61; p = 1.15 × 10-9). CONCLUSION: Older age, higher body mass index, and a more significant PI-LL mismatch were associated with unfavorable results on functional scales. We found a genetic variation in the SVIL gene, which has been associated with the integrity of the cytoskeleton and the development of skeletal muscles, in severe ASD phenotypes. Our results help to elucidate the pathogenesis of ASD.

A Comparison of fixed-hole and slotted-hole dynamic plates for anterior cervical discectomy and fusion.

STUDY DESIGN: A retrospective review of clinical data at 1 institution was performed. OBJECTIVES: To compare the clinical and radiologic outcomes between fixed-hole and slotted-hole dynamic cervical plates. SUMMARY OF BACKGROUND DATA: Anterior cervical plating is commonly used to increase stability and promote spinal fusion. Two techniques, fixed-hole dynamic plating that uses variable angled screws and slotted-hole dynamic plating that permits sliding, are viable options, but there have been no clinical studies comparing their effectiveness. METHODS: Fifty-six patients at 1 institution having anterior cervical discectomy and fusion for degenerative disease over a 5-year period were entered into this study. Surgeries were performed with 1 of the dynamic plates for 1 to 3 levels. For the slotted-hole dynamic plate group, a slotted-hole plate was used (ABC, Aesculap, Tuttlingen, Germany or C-tek, Biomet, Parssipany, NJ) and for the fixed-hole dynamic plated group, a variable angled screw was used (C-tek, Biomet, Parssipany, NJ). Radiographic measurements included were graft subsidence, lordotic angle change from each end plate of fusion construct, and implant translation from end plates after a minimum of 12 months follow-up. Fusion state and clinical outcome using Odom's criteria were also evaluated. RESULTS: Demographics were not different among patient populations. The average age of the patients was 51.0 years (range: 27 to 77 y). Mean follow-up period was 20.6 months (range: 12 to 41 mo). Slotted-hole dynamic plates were used for 29 patients (ABC plate, 17; C-tek plate, 12) and fixed-hole dynamic plates for 27 patients. Clinical outcomes and pseudoarthrosis rates were similar for both types of plates. Radiographic measurements showed a statistically significant increased incidence of graft subsidence and implant translation with the slotted-hole dynamic plates. Loss of lordosis was also greater in the slotted-hole dynamic plated group, although the difference was not statistically significant. CONCLUSIONS: The use of a fixed-hole dynamic plate is more favorable in regards to graft subsidence and implant translation in the follow-up period, although clinical outcome and fusion rates are similar in patients with either the fixed-hole or slotted-hole dynamic plates.

Activin A and BMP chimera (AB204) induced bone fusion in osteoporotic spine using an ovariectomized rat model.

BACKGROUND CONTEXT: Recombinant human bone morphogenic protein 2 (rhBMP2) has been used to induce bone fusion in patients with spinal fusion surgery. However, the effectiveness of rhBMP2 in the bone fusion process is limited in osteoporosis patients, and a high dose of rhBMP2 for enough bone fusion sometimes provokes side effects. Therefore, substitutes for rhBMP2 with a higher therapeutic potency are needed, and already several studies have published the effectiveness of Activin A/BMP2 chimera (AB204) in new bone formation process in vitro and in vivo. PURPOSE: In the present study, we provide evidence that bone fusion activity of AB204 is superior to that of rhBMP2 in osteoporotic rat models. STUDY DESIGN/SETTINGS: An in vivo animal study was carried out. METHODS: A total of 40 Sprague-Dawley rats underwent bilateral ovariectomy. At 6 weeks after ovariectomy, a lumbar spinal bone fusion model of bilateral intertransverse process was performed. All rats were randomly divided into four groups as follows: rats receiving 5 µg of rhBMP2 (Group I), rats receiving 10 µg of rhBMP2 (Group II), rats receiving 5 µg of AB204 (Group III), and rats receiving 10 µg of AB204 (Group IV). Simple radiographs were performed at 6 and 12 weeks after bone fusion, and direct palpation, micro-CT, and immunohistochemistry (hematoxylin-eosin stain and Masson's trichrome stain) were performed at 12 weeks after bone fusion. The qualitative degree of bone fusion was assessed as manual fusion score from direct palpation, and radio-histologic fusion score from simple radiographs, micro-CT, and immunohistochemistry. Also, the quantitative degree of bone fusion was assessed using fusion bone volume by micro-CT and serum osteocalcin level as bone turnover markers. RESULTS: The change of body weight was not different among the groups during follow-up. The qualitative degree of bone fusion assessed by direct palpation, simple radiographs, micro-CT, and histologic evaluation was significantly different among the four groups. Also, the quantitative degree of bone fusion including fusion bone volume and serum osteocalcin was significantly different among the groups. Especially, in manual fusion score, radio-histologic fusion score, and fusion bone volume, the AB204 group revealed superior results to the rhBMP2 group when using the same dose. Furthermore, even the low-dose AB204 group (Group III) showed superior results to the high-dose rhBMP2 group (Group II) in radio-histologic fusion score and fusion bone volume. CONCLUSION: The effect of bone fusion in osteoporotic rats was significantly higher in the AB204 group than in the rhBMP2 group. CLINICAL SIGNIFICANCE: If further organized animal studies and clinical trials are provided, AB204 may be a good substitute for rhBMP2 in osteoporotic spinal fusion surgery, as a superior osteogenesis inducer.

The combined effect of granulocyte-colony stimulating factor (G-CSF) treatment and exercise in rats with spinal cord injury.

Objective: To identify that the combined G-CSF and treadmill exercise is more effective in functional recovery after spinal cord injury (SCI).Design: Rats were divided into 4 groups: a SCI group treated with G-CSF (G-CSF group, n = 6), a SCI group treated with treadmill exercise plus G-CSF (G-CSF/exercise group, n = 6), a SCI group with treadmill exercise (exercise group, n = 6), and a SCI group without treatments (control group, n = 6). We performed laminectomy at the T8-10 spinal levels with compression injury of the spinal cord in all rats. G-CSF (20 µg/ml) was administered intraperitoneally for 5 consecutive days after SCI in G-CSF and G-CSF/exercise groups. From one week after surgery, animals in G-CSF/exercise and exercise groups received 30 min of exercise 5 days per week for 4 weeks. Functional recoveries were assessed using the Basso, Beattie, and Bresnahan (BBB) scale and the inclined plane test. Five weeks after SCI, hematoxylin and eosin staining for cavity size and immunohistochemistry for glial scar formation and neuro-regeneration factor expression were conducted.Setting: Inha University School of medicine, Incheon, KoreaResults: Rats in G-CSF/exercise group showed the most effective functional recovery in the BBB scale and the inclined plane test, and spinal cord cavity size by injury were the smallest, and immunohistochemistry revealed expression of higher BDNF (brain-derived neurotrophic factor) and VEGF (vascular endothelial growth factor) and lower GFAP (glial fibrillary acidic protein) than others.Conclusion: Combined treatment provided more effective neuroplasty and functional recovery than individual treatments.

Natural history and aggravating factors of sagittal imbalance in marked sagittal deformity compared with mild to moderate sagittal deformity: A prospective cohort study.

Sagittal imbalance is a multifactorial complex deformity that can arise from a variety of causes such as spinal stenosis, sarcopenia, vertebral fracture, and neuromuscular diseases. Furthermore, there is lack of research regarding spinal and general conditions that precede the development of sagittal imbalance. Our aim was to evaluate aggravating factors, such as natural history, for sagittal imbalance in a cohort comprising elderly individuals by conducting various examinations.We recruited 96 participants who had a sagittal vertical axis (SVA) larger than 50 mm in a sagittal imbalance study. Finally, 69 participants were followed up and enrolled this study after 2 years. We evaluated full spine radiographs, magnetic resonance imaging (MRI), bone mineral density, and health-related quality of life from patients survey and analyzed factors associated with aggravation of sagittal imbalance. Aggravation was defined by an SVA > 30 mm and T1 pelvic angle (T1PA) > 3° in the third year compared to SVA and T1PA values of the first year.Eighteen participants of the follow-up group had a sagittal imbalance aggravation. According to the deformity severity in the first-year evaluations, the marked deformity group (38 participants) defined as Schwab classification had 11 (28.9%) participants presenting with sagittal imbalance aggravation. These participants had larger mean values of Schwab sagittal modifiers and T1PA compared with the nonaggravation participants. Logistic regression analysis showed a higher pelvic incidence (PI) (OR = 1.201, 95% CI = 1.015-1.422, P = .033) and a small multifidus (MF) volume (OR = 0.991, 95% CI = 0.983-1.000, P = .043) correlated with sagittal imbalance aggravation.From the follow-up group, 18 (26%) subjects of total 69 participants presented a deteriorated sagittal imbalance. A higher PI and smaller MF volume correlated with the aggravation of sagittal imbalance. We should consider that high PI and small MF volume are associated with aggravation of sagittal imbalance.

GM-CSF inhibits glial scar formation and shows long-term protective effect after spinal cord injury.

OBJECT: This study investigated the effects of granulocyte macrophage-colony stimulating factor (GM-CSF) on the scar formation and repair of spinal cord tissues in rat spinal cord injury (SCI) model. METHODS: Sprague-Dawley male rats (8 weeks old) were randomly divided into the sham-operated group, spinal cord injury group, and injury with GM-CSF treated group. A spinal cord injury was induced at T9/10 levels of rat spinal cord using a vascular clip. GM-CSF was administrated via intraperitoneal (IP) injection or on the dural surface using Gelfoam at the time of SCI. The morphological changes, tissue integrity, and scar formation were evaluated until 4 weeks after SCI using histological and immunohistochemical analyses. RESULTS: The administration of GM-CSF either via IP injection or local treatment significantly reduced the cavity size and glial scar formation at 3-4 weeks after SCI. GM-CSF also reduced the expression of core proteins of chondroitin sulfate proteoglycans (CSPGs) such as neurocan and NG2 but not phosphacan. In particular, an intensive expression of glial fibriallary acidic protein (GFAP) and neurocan found around the cavity at 4 weeks was obviously suppressed by GM-CSF. Immunostaining for neurofilament (NF) and Luxol fast blue (LFB) showed that GM-CSF preserved well the axonal arrangement and myelin structure after SCI. The expression of GAP-43, a marker of regenerating axons, also apparently increased in the rostral grey matter by GM-CSF. CONCLUSION: These results suggest that GM-CSF could enhance long-term recovery from SCI by suppressing the glial scar formation and enhancing the integrity of axonal structure.

Graft Perforation by a Spinal Bony Spur: An Unusual Cause of Late Bleeding after Thoracoabdominal Aorta Replacement.

We report an unusual case of delayed bleeding after open surgical repair of a thoracoabdominal aortic aneurysm. A 79-year-old man developed a massive retroperitoneal hematoma 49 days after Crawford type III thoracoabdominal aorta replacement. During emergency surgery, a tear was found in the prosthetic vascular graft caused by a sharp bony spur arising from the second lumbar vertebral body. This rare, but potentially lethal, complication indicates that attention should be paid to sharp bony structures during open repair of the descending aorta.

Is Adjacent Segment Disease More Frequent in Proximal Levels in Comparison with Distal Levels? Based on Radiological Data of at Least 2 Years Follow Up with More than 2 Level Thoracolumbar Fusions.

OBJECTIVE: The purpose of this retrospective study was to determine which of the proximal adjacent segment disease (ASD) and distal ASD was more prevalent and what parameters is more related to ASD in proximal levels and distal levels after more than 2 levels fusions. METHODS: The medical records were reviewed retrospectively for 856 cases. A total of 66 cases of ASD were enrolled. On preop magnetic resonance imaging, disc degeneration was measured at the upper and lower parts of surgically treated levels and confirmed by the commonly used Pfirrmann grade. Segmental flexibility in sagittal plane was embodied in segment range of motion (ROM) obtained through flexion and extension X-ray before surgery. Coronal angle was recorded as methods Cobb's angle including fusion levels preoperatively. For the comparison of categorical variables between two independent groups, the chi-square test and Fisher exact test were performed. RESULTS: Proximal ASD and distal ASD were 37/856 (4.32%) and 29/856 (3.39%), respectively. The incidence of proximal ASD was relatively high but insignificant differences. In comparison between ASD group and non ASD group, proximal Pfirmman was higher in proximal ASD and distal Pfirmman was higher in distal ASD group (p=0.005, p<0.008, respectively). However, in the ROM, proximal ROM was higher in proximal ASD, but distal ROM was not different between the two groups (p<0.0001, p=0.995, respectively). Coronal angle was not quite different in both groups (p=0.846). CONCLUSION: In spite of higher frequency in ASD in proximal level in spinal fusion, it is not clear that incidence of ASD in proximal level is not higher than that of distal ASD group in more than 2 level thoracolumbar fusions. Not only Pfirrmann grade but also proximal segmental ROM is risk factor for predicting the occurrence of ASD in patients more than 2 level of thoracolumbar spine fusion operation excluding L5S1.

Clinical Outcomes of Surgical Treatment for Primary Chest Wall Soft Tissue Sarcoma.

BACKGROUND: This study investigated the clinical outcomes of surgical treatment of primary chest wall soft tissue sarcoma (CW-STS). METHODS: Thirty-one patients who underwent surgery for CW-STS between 2000 and 2015 were retrospectively reviewed. The disease-free and overall survival rates were estimated using the Kaplan-Meier method, and prognostic factors were analyzed using a Cox proportional hazards model. RESULTS: The median follow-up duration was 65.6 months. The most common histologic type of tumor was malignant fibrous histiocytoma (29%). The resection extended to the soft tissue in 14 patients, while it reached full thickness in 17 patients. Complete resection was achieved in 27 patients (87.1%). There were 5 cases of local recurrence, 3 cases of distant metastasis, and 5 cases of combined recurrence. The 5-year disease-free rate was 49%. Univariate analysis indicated that incomplete resection (p<0.001) and stage (p=0.062) were possible risk factors for recurrence. Multivariate analysis determined that incomplete resection (p=0.013) and stage (p=0.05) were significantly associated with recurrence. The overall 5- and 10-year survival rates were 86.8% and 64.3%, respectively. No prognostic factor for survival was identified. CONCLUSION: Long-term primary CW-STS surgery outcomes were found to be favorable. Incomplete microscopic resection and stage were risk factors for recurrence.

Prospective Observational Cohort Study of Health-related Quality of Life: Marked Adult Sagittal Deformity (ASD) in Comparison With Mild to Moderate ASD.

STUDY DESIGN: Retrospective analysis of prospective observational cohort OBJECTIVE.: This study assessed the difference in health-related quality of life (HRQOL) between participants with a mild to moderate adult sagittal deformity (ASD) (sagittal vertical axis [SVA] ≤9.5 cm) and those with a marked deformity (SVA >9.5 cm). We also evaluated predisposing factors for a marked deformity. SUMMARY OF BACKGROUND DATA: Sagittal imbalance is closely associated with HRQOL for the patient. However, how the effect changes depending on the degree of imbalance has not been fully evaluated. The understanding of the predisposing factor associated with marked deformity also lacks. METHODS: A total of 124 elderly persons with a stooping posture were enrolled. Questionnaires related to HRQOL were administered. Sagittal alignment parameters and pelvic parameters were measured with a whole spine x-ray. Lumbar spine magnetic resonance imaging was used to assess the presence of pathologic conditions, muscle quality and quantity. Multivariate logistic regression analysis was conducted to analyze potential risk factors. RESULTS: Marked ASD was associated with female sex, lower height and weight, and osteoporosis (P < 0.05). Back pain (assessed by a visual analogue scale) and the Oswestry Disability Index were significantly higher in the marked deformity group (P = 0.012, 0.002, respectively). Multivariate logistic regression analysis showed significant relationships between the following parameters and marked deformity: preexisting compression fracture (odds ratio [OR] = 7.793; 95% confidence interval [CI], 1.527-39.768), severe L5/S1 Pfirrmann disc degeneration grade (OR = 1.916; 95% CI, 1.086-3.382), and lower quantities of multifidus and psoas muscles (OR = 0.994, 0.997; 95% CI, 0.991-0.998, 0.994-0.999, respectively). CONCLUSION: Participants with a marked ASD showed different features from those with a mild to moderate ASD. This study also implies that anatomical factors, including the vertebrae, intervertebral discs, and paraspinal muscles, synergistically contribute to progression into marked deformity. LEVEL OF EVIDENCE: 3.

A porcine model of intervertebral disc degeneration induced by annular injury characterized with magnetic resonance imaging and histopathological findings. Laboratory investigation.

OBJECT: Appropriate animal models of disc degeneration are critical for the study of proposed interventions as well as to further delineate the degenerative process. The purpose of this study was to characterize a porcine model for disc degeneration confirmed on magnetic resonance (MR) imaging studies and histological analysis. METHODS: Twelve miniature pigs were used (weight 48-65 kg) to study degeneration in the lumbar spine. Under fluoroscopic guidance, the disc was percutaneously punctured with a 3.2-mm-diameter trephine to a 5-mm depth into the annulus fibrosus. Control and experimental levels were randomized among 6 levels in the lumbar spine. The unlesioned spinal levels were used as controls and were compared with lesioned levels. Magnetic resonance imaging grading and disc height were serially recorded preoperatively, and at 5, 8, 19, 32, and 39 weeks postoperatively. The animals were killed in groups of 3 at 7, 18, 32, and 41 weeks postinjury, and the discs were examined histopathologically. RESULTS: Consistent, sequential, and progressive degeneration of the annular injury was observed on MR imaging and histopathological studies from the time of injury to the final time point. The disc height and the disc height index also sequentially decreased from the time of the injury in a consistent manner. The uninjured control levels did not show any progressive degeneration and maintained their normal state. CONCLUSIONS: Based on MR imaging and histopathological findings, the authors demonstrated and characterized a reliable model of sequential disc degeneration in miniature pigs with percutaneous injury to the annulus fibrosus. In the early stages, as soon as 5 weeks after injury, significant disc degeneration was seen on MR imaging grading with decreases in disc height. This degeneration did not improve by the final time point of 39 weeks.

Activin A/BMP2 Chimera (AB204) Exhibits Better Spinal Bone Fusion Properties than rhBMP2.

OBJECTIVE: To compare the spinal bone fusion properties of activin A/BMP2 chimera (AB204) with recombinant human bone morphogenetic protein (rhBMP2) using a rat posterolateral spinal fusion model. METHODS: The study was designed to compare the effects and property at different dosages of AB204 and rhBMP2 on spinal bone fusion. Sixty-one male Sprague-Dawley rats underwent posterolateral lumbar spinal fusion using one of nine treatments during the study, that is, sham; osteon only; 3.0 µg, 6.0 µg, or 10.0 µg of rhBMP2 with osteon; and 1.0 µg, 3.0 µg, 6.0 µg, or 10.0 µg of AB204 with osteon. The effects and property on spinal bone fusion was calculated at 4 and 8 weeks after treatment using the scores of physical palpation, simple radiograph, micro-computed tomography, and immunohistochemistry. RESULTS: Bone fusion scores were significantly higher for 10.0 µg AB204 and 10.0 µg rhBMP2 than for osteon only or 1.0 µg AB204. AB204 exhibited more prolonged osteoblastic activity than rhBMP2. Bone fusion properties of AB204 were similar with the properties of rhBMP2 at doses of 6.0 and 10.0 µg, but, the properties of AB204 at doses of 3.0 µg exhibited better than the properties of rhBMP2 at doses of 3.0 µg. CONCLUSION: AB204 chimeras could to be more potent for treating spinal bone fusion than rhBMP2 substitutes with increased osteoblastic activity for over a longer period.

Transplantation of human bone marrow-derived clonal mesenchymal stem cells reduces fibrotic scar formation in a rat spinal cord injury model.

This study aimed to evaluate the therapeutic effect on tissue repair and scar formation of human bone marrow-derived clonal mesenchymal stem cells (hcMSCs) homogeneously isolated by using a subfractionation culturing method, in comparison with the non-clonal MSCs (hMSCs), in a rat spinal cord injury (SCI) model. The SCI was made using a vascular clip at the T9 level. Cells were transplanted into the lesion site 3 days after injury. A functional test was performed over 4 weeks employing a BBB score. Rats were killed for histological analysis at 3 days, 1 week and 4 weeks after injury. The transplantation of hMSCs and hcMSCs significantly reduced lesion size and the fluid-filled cavity at 4 weeks in comparison with the control group injected with phosphate buffered saline (PBS) (p < 0.01). Transplantation of hcMSCs showed more axons reserved than that of hMSCs in the lesion epicentre filled with non-neuronal tissues. In addition, hMSCs and hcMSCs clearly reduced the inflammatory reaction and intraparenchymal hemorrhaging, compared with the PBS group. Interestingly, hcMSCs largely decreased Col IV expression, one of the markers of fibrotic scars. hcMSCs yielded therapeutic effects more than equal to those of hMSCs on the SCI. Both hMSCs and hcMSCs created an increase in axon regeneration and reduced scar formation around the SCI lesion. Copyright © 2017 John Wiley & Sons, Ltd.