Highly Porous Titanium Cups Frequently Presenting with Radiolucent Lines in Cementless Primary Total Hip Arthroplasty: A Retrospective Cohort Study.

Background/Objectives: A highly porous titanium cup with a three-dimensional metal interface was recently introduced to improve biological fixation and survival. However, radiography has revealed concerns regarding these cups, despite their excellent short- and mid-term clinical outcomes. This study compared the clinical and radiographic results of a highly porous titanium cup with those of a hydroxyapatite-coated porous titanium cup after primary total hip arthroplasty (THA). Methods: Fifty-one primary THAs were investigated. A highly porous titanium cup was used in 17 hips, and a hydroxyapatite-coated porous titanium cup was used in 34 hips. No significant differences in preoperative patient demographic characteristics were observed between the two groups. The 2-year postoperative clinical and radiographic results were compared. Results: Radiolucent lines were observed in 13 (76%) of 17 hips with highly porous titanium cups and in none (0%) of 34 hips with hydroxyapatite-coated porous titanium cups (p < 0.001). In the highly porous titanium cup group, radiolucent lines were observed in five hips (29%) in one zone, two hips (11%) in two zones, and six hips (35%) in three zones. No cup loosening was observed in either group. Conclusions: Radiolucent lines were significantly more frequent in highly porous titanium cups. This study suggests that, compared to the three-dimensional structure of porous titanium, the hydroxyapatite coating of porous titanium had a greater influence on bone ingrowth in the short term. The meaning of these findings in the long-term is unclear yet.

The Validation of the Japanese Version of the Scoliosis Research Society-30 Questionnaire for Adolescent Idiopathic Scoliosis Patients.

Introduction: The Scoliosis Research Society-30 (SRS-30) is a questionnaire originally developed from the SRS-22r questionnaire and is used to evaluate adolescent idiopathic scoliosis (AIS). It comprised questions on five domains: function, pain, self-image, mental health, and satisfaction, with seven additional questions related to postoperative aspects. In addition to the original English version, translations in multiple languages have been effectively applied. Herein, we evaluated the internal consistency and external validity of the Japanese version of the SRS-30 for AIS patients. Methods: Among the 30 questions in SRS-30, the eight additional questions from SRS-22r were translated and back-translated to create a Japanese version of the SRS-30. This translated questionnaire was then used to survey patients with AIS who underwent corrective fusion surgery one year postoperatively. The internal consistency of the responses was evaluated using the Cronbach α coefficient. Additionally, the Spearman correlation analyses were conducted to assess the correlation between the scores obtained from the SRS-30 Japanese version and SRS-22r and the Oswestry Disability Index (ODI) for the overall scale and the five domains. Results: A total of 81 cases (eight males and 73 females; mean age at surgery 14.4 years) were enrolled. The mean preoperative Cobb angle was 51.0°. The Cronbach α coefficient for the overall SRS-30 was 0.861, indicating high internal consistency, while the coefficients for each domain were as follows: function/activity, 0.697; pain, 0.405; self-image/appearance, 0.776; mental health, 0.845; and satisfaction, 0.559. The SRS-30 total score significantly correlated with the SRS-22r total (r=0.945, P<0.001) and the ODI (r=-0.511, P<0.001). The SRS-30 domains highly correlated with the corresponding SRS-22r domains, with correlations ranging from r=0.826 to 0.901 (all P<0.001). Conclusions: The Japanese version of the SRS-30 demonstrated good internal and external validity. The SRS-30 can be used as an assessment tool for health-related quality of life in AIS patients.

Assessing the Impact of Preoperative MRI-Based Vertebral Bone Quality Scores on 5-Year Prognosis in Lumbar Spine Surgery.

STUDY DESIGN: Retrospective cohort study. OBJECTIVE: To assess the utility of preoperative vertebral bone quality (VBQ) scores in predicting the 5-year clinical outcomes following lumbar spine surgery. SUMMARY OF BACKGROUND DATA: Osteoporosis poses a significant concern in older adults undergoing spinal surgery. The VBQ score, assessed through preoperative magnetic resonance imaging (MRI), is associated with subsequent osteoporotic fractures and postoperative complications. However, previous report on the impact of VBQ score on mid-term clinical outcomes after lumbar spine surgery remains lacking. METHODS: A total of 189 patients who underwent lumbar surgery (≤3-disc levels) for lumbar spinal stenosis between 2010 and 2016 were enrolled. Patients were classified into high (>3.35), middle (2.75 to 3.35), and low (<2.73) VBQ score groups based on tertiles. Clinical scores, including Japanese Orthopedic Association Back Pain Evaluation Questionnaire (JOABPEQ) and Short Form-36 (SF-36), were recorded preoperatively and 1, 2, and 5 years postoperatively. RESULTS: Comparative analysis showed significant differences among the VBQ groups throughout the study period in low back pain (P=0.013), walking ability (P=0.005), social life function (P=0.010) of JOABPEQ, and physical component summary of the SF-36 (P=0.018) following lumbar spine surgery. A higher VBQ score was significantly correlated with worse 5-year postoperative outcomes for all domains except for lumbar function of the JOABPEQ using multiple linear regression analysis, adjusting for age, sex, BMI, hyperlipidemia, surgical procedures, and each preoperative score. CONCLUSION: A high preoperative VBQ score is a risk factor for poor 5-year clinical outcomes after lumbar spine surgery. Evaluation of the VBQ score through routine preoperative MRI facilitates osteoporotic screening in lumbar patients without radiation exposure and healthcare costs, while also demonstrating its potential as a prognostic indicator of postoperative clinical outcomes. LEVEL OF EVIDENCE: 3.

Risk Factors for Residual Back Pain After Balloon Kyphoplasty for Osteoporotic Vertebral Fracture.

Background: Balloon kyphoplasty (BKP) is a method for the management of osteoporotic vertebral body fracture (OVF). However, improvement in back pain (BP) is poor in some patients, also previous reports have not elucidated the exact incidence and risk factors for residual BP after BKP. We clarified the characteristics of residual BP after BKP in patients with OVF. Hypothesis: In this study, we hypothesize that some risk factors may exist for residual BP 2 years after the treatment of OVF with BKP. Patients and Methods: A multicenter cohort study was performed where patients who received BKP within 2 months of OVF injury were followed-up for 2 years. BP at 6 months after surgery and final observation was evaluated by Visual Analog Scale (VAS) score. Patients with a score of 40 mm or more were allocated to the residual BP group, and comparisons between the residual back pain group and the improved group were made for bone density, kyphosis, mobility of the fractured vertebral body, total spinal column alignment, and fracture type (fracture of the posterior element, pedicle fracture, presence or absence of posterior wall damage, etc.). Also, Short Form 36 (SF-36) for physical component summary (PCS) and mental component summary (MCS) at the final follow-up was evaluated in each radiological finding. Results: Of 116 cases, 79 (68%) were followed-up for 2 years. Two years after the BKP, 26 patients (33%) experienced residual BP. Neither age nor sex differed between the groups. In addition, there was no difference in bone mineral density, BKP intervention period (period from onset to BKP), and osteoporosis drug use. However, the preoperative height ratio of the vertebral body was significantly worse in the residual BP group (39.8% vs. 52.1%; p = 0.007). Two years after the operation, the vertebral body wedge angle was significantly greater in the residual BP group (15.7° vs. 11.9°; p = 0.042). In the multiple logistic regression model with a preoperative vertebral body height ratio of 50% or less [calculated by receiver operating characteristic (ROC) curve], the adjusted odds ratio for residual BP was 6.58 (95% confidence interval 1.64-26.30; p = 0.007); similarly, patients with vertebral body height ratio less than 50% had a lower score of SF-36 PCS 24.6 vs. 32.2 p = 0.08. Conclusion: The incidence of residual BP 2 years after BKP was 33% in the current study. The risk factor for residual BP after BKP was a preoperative vertebral body height ratio of 50% or less, which should be attentively assessed for the selection of a proper treatment scheme and to provide adequate stabilization. Level of Evidence: III.

Assessment of toxic effects of imidacloprid on freshwater zooplankton: An experimental test for 27 species.

The neonicotinoid pesticide imidacloprid has been used worldwide since 1992. As one of the most important chemicals used in pest control, there have been concerns that its run-off into rivers and lakes could adversely affect aquatic ecosystems, where zooplankton play a central role in the energy flow from primary to higher trophic levels. However, studies assessing the effects of pesticides at the species level have relied on a Daphnia-centric approach, and no studies have been conducted using species-level assessments on a broad range of zooplankton taxa. In the present study, we therefore investigated the acute toxicity of imidacloprid on 27 freshwater crustacean zooplankton (18 cladocerans, 3 calanoid copepods and 6 cyclopoid copepods). The experiment showed that a majority of calanoid copepods and cladocerans were not affected at all by imidacloprid, with the exception of one species each of Ceriodaphnia and Diaphasoma, while all six cyclopoid copepods showed high mortality rates, even at concentrations of imidacloprid typically found in nature. In addition, we found a remarkable intra-taxonomic variation in susceptibility to this chemical. As many cyclopoid copepods are omnivorous, they act as predators as well as competitors with other zooplankton. Accordingly, their susceptibility to imidacloprid is likely to cause different responses at the community level through changes in predation pressure as well as changes in competitive interactions. The present results demonstrate the need for species-level assessments of various zooplankton taxa to understand the complex responses of aquatic communities to pesticide disturbance.

Impact of Incident Osteoporotic Vertebral Fractures on 5-Year Postoperative Outcomes and Spinal Alignment Following Lumbar Fusion Surgery.

Introduction: Osteoporotic vertebral fractures (OVFs) are a significant problem among older patients who are undergoing spine surgery. This study examined the influence of incident OVFs on clinical outcomes and spinal alignment 5 years following short-segment fusion (SSF) for lumbar spinal stenosis. Methods: We studied 88 patients who underwent SSF (≤2-disc level) for lumbar spinal stenosis with instability and were followed up for more than 5 years postoperatively. Those with prior OVFs were excluded. We evaluated incident OVFs with plain whole-spine lateral radiography preoperatively (before) and at 5 years postoperatively (after). Using preoperative lumbar computed tomography, Hounsfield unit (HU) values were evaluated. The patients were classified into two groups according to the presence of incident OVFs. Repeated-measures analysis of variance was utilized to compare the Japanese Orthopaedic Association Back Pain Evaluation Questionnaire (JOABPEQ) and the 36-item Short-Form Health Survey (SF-36), and spinal parameters were recorded before and after. Multiple linear regression analyses were employed to investigate the association between the incident OVFs and the clinical scores and spinal alignment recorded after. Results: In the fracture group, the clinical course of low back pain score on the JOABPEQ, physical component summary SF-36 score, and spinal alignment including C7 sagittal vertical axis (SVA), thoracic kyphosis (TK), and pelvic tilt were significantly worse. Multiple linear regression revealed a significant correlation between incident OVFs and worse 5-year postoperative spinal alignment, which includes SVA and TK. The optimal threshold for the HU values for predicting the incidence of OVFs within 5 years postoperatively was 83.0 (area under the curve 0.701). Conclusions: Incident OVFs in patients following SSF were significantly correlated with the 5-year clinical outcomes and spinal alignment. Patients at risk of OVFs, especially those with HU values below 83, must take preventive measures against OVFs, as this could prevent deteriorating midterm postoperative clinical outcomes and spinal alignment. Level of Evidence: 3.

Degeneration of Cervical Multifidus Muscles Negatively Affects Physical Activity-related Quality of Life After Laminoplasty for Degenerative Cervical Myelopathy.

STUDY DESIGN: A retrospective cohort study. OBJECTIVE: The study aimed to investigate the related factors affecting physical activity-related quality of life (QOL) after 2 years of cervical laminoplasty for degenerative cervical myelopathy (DCM), focusing on the degree of preoperative degeneration of the cervical multifidus muscles. SUMMARY OF BACKGROUND DATA: The association between paraspinal muscle degeneration and clinical outcomes after spinal surgery is being investigated. The effect of preoperative degeneration of the cervical multifidus muscles in patients undergoing cervical laminoplasty is ambiguous. METHODS: Patients who underwent laminoplasty for DCM and followed up for more than 2 years were reviewed. To evaluate physical QOL, the physical component summary (PCS) of the 36-Item Short-Form Health Survey (SF-36) was recorded at 2 years postoperatively. The degree of preoperative degeneration in the multifidus muscles at the C4 and C7 levels on axial T2-weighted magnetic resonance imaging (MRI) was categorized according to the Goutallier grading system. The correlation between 2-year postoperative PCS and each preoperative clinical outcome, radiographic parameter, and MRI finding, including Goutallier classification, was analyzed. Variables with a P value <0.10 in univariate analysis were included in multiple linear regression analysis. RESULTS: In total, 106 consecutive patients were included. The 2-year postoperative PCS demonstrated significant correlation with age (R=-0.358, P=0.002), preoperative JOA score (R=0.286, P=0.021), preoperative PCS (R=0.603, P<0.001), C2-C7 lordotic angle (R=-0.284, P=0.017), stenosis severity (R=-0.271, P=0.019), and Goutallier classification at the C7 level (R=-0.268, P=0.021). In multiple linear regression analysis, sex (ß=-0.334, P=0.002), age (ß=-0.299, P=0.013), preoperative PCS (ß=0.356, P=0.009), and Goutallier classification at the C7 level (ß=-0.280, P=0.018) were significantly related to 2-year postoperative PCS. CONCLUSIONS: Increased degeneration of the multifidus muscle at the C7 level negatively affected physical activity-related QOL postoperatively. These results may guide spine surgeons in predicting physical activity-related QOL in patients with DCM after laminoplasty. LEVEL OF EVIDENCE: Level III.

Recovery of phosphorus, magnesium, and potassium from surplus activated sludge using existing sludge treatment facilities and thickened primary sludge.

The separation of P, K, and Mg from surplus activated sludge (SAS) was investigated using existing sludge treatment facilities and the thickened primary sludge (TPS). The addition of the TPS to the SAS storage tank accelerated the anaerobic release of the three elements from SAS with maximum efficiencies of about 60%. The efficiency of P release showed a significant correlation with the oxidation-reduction potential. Increasing the total solid concentration increased the release of elements. The released elements could be transferred to a separate liquid (SL) from a screw-press thickener, and maximum concentrations of P, K, and Mg were about 200, 60, and 35 mg/L, respectively. The addition of CaCl2 and NaOH solutions to SL precipitated P as hydroxyapatite. However, no precipitation of K and Mg occurred simultaneously with P, even when the pH of SL was increased to 9. These findings suggest that about 60% of P, K, and Mg can be separated from SAS into SL using existing sludge treatment facilities and TPS; however, a method other than precipitation would be needed to recover P and K from SL simultaneously.

Short-Term Risk Factors for Distal Junctional Kyphosis after Spinal Reconstruction Surgery in Patients with Osteoporotic Vertebrae.

STUDY DESIGN: Level 3 retrospective cohort case-control study. PURPOSE: This study aimed to investigate the risk factors for distal junctional kyphosis (DJK) caused by osteoporotic vertebral fractures following spinal reconstruction surgery, with a focus on the sagittal stable vertebra. OVERVIEW OF LITERATURE: Despite the rarity of reports on DJK in this setting, DJK was reported to reduce when the lower instrumented vertebra (LIV) was extended to the sagittal stable vertebra in the posterior corrective fixation for Scheuermann's disease. METHODS: This study included 46 patients who underwent spinal reconstruction surgery for thoracolumbar osteoporotic vertebral fractures and kyphosis and were followed up for 1 year postoperatively. DJK was defined as an advanced kyphosis angle >10° between the LIV and one lower vertebra. The patients were divided into groups with and without DJK. The risk factors of the two groups, such as patient background, surgery-related factors, radiographic parameters, and clinical outcomes, were analyzed. RESULTS: The DJK and non-DJK groups included 14 and 32 patients, respectively, without significant differences in patient background. Those with instability in the distal adjacent LIV disc had a significantly higher risk of DJK occurrence (28.6% vs. 3.2%, p=0.027). DJK occurrence significantly increased in those with the sagittal stable vertebra not included in the fixation range (57.1% vs. 18.8%, p=0.020). Other preoperative radiographic parameters were not significantly different. Instability in the distal adjacent LIV disc (adjusted odds ratio, 14.50; p=0.029) and the exclusion of the sagittal stable vertebra from the fixation range (adjusted odds ratio, 5.29; p=0.020) were significant risk factors for DJK occurrence. CONCLUSIONS: Regarding spinal reconstruction surgery in patients with osteoporotic vertebral fractures, instability in the distal adjacent LIV disc and the exclusion of the sagittal stable vertebra from the fixation range were risk factors for DJK occurrence in the short term.

Lower preoperative Hounsfield unit values as a risk factor for poor 5-year clinical outcomes after lumbar spine surgery.

OBJECTIVE: Hounsfield Unit (HU) value has been associated with future osteoporotic fractures and postoperative complications. However, no studies on the impact of low HU values on mid-term clinical outcomes following lumbar spine surgery have been reported. We aimed to evaluate the usefulness of preoperative HU values for 5-year clinical outcomes following lumbar spine surgery. METHODS: We enrolled 200 patients who underwent lumbar surgery (≤ 3-disc levels) for lumbar spinal stenosis. HU values were assessed using preoperative lumbar computed tomography as part of routine preoperative planning for lumbar surgery. Patients were divided into two groups based on the cutoff value of the HU values obtained from the receiver operating characteristic curve for the incidence of vertebral fractures within five years postoperatively. Clinical scores preoperatively and 1, 2, and 5 years postoperatively, including Japanese Orthopedic Association Back Pain Evaluation Questionnaire (JOABPEQ) and Short Form-36 (SF-36), were compared using a mixed-effects model. RESULTS: Comparative analysis indicated that all domains of JOABPEQ, except for lumbar function, and the physical component summary of the SF-36 were significantly worse in the low HU group than in the high HU group. Using multiple regression analysis, low HU values were significantly correlated with worse 5-year postoperative scores in all domains of JOABPEQ and SF-36. CONCLUSION: Low preoperative HU values are a risk factor for poor 5-year clinical outcomes after lumbar spine surgery. HU values are not only a valuable tool for analyzing bone mineral density but also may be a valuable poor prognostic factor of postoperative clinical outcomes.

Discovery of novel indole derivatives as potent and selective inhibitors of proMMP-9 activation.

Matrix metalloproteinase-9 (MMP-9) is a secreted zinc-dependent endopeptidase that degrades the extracellular matrix and basement membrane of neurons, and then contributes to synaptic plasticity by remodeling the extracellular matrix. Inhibition of MMP-9 activity has therapeutic potential for neurodegenerative diseases such as fragile X syndrome. This paper reports the molecular design, synthesis, and in vitro studies of novel indole derivatives as inhibitors of proMMP-9 activation. High-throughput screening (HTS) of our internal compound library and subsequent merging of hit compounds 1 and 2 provided compound 4 as a bona-fide lead. X-ray structure-based design and subsequent lead optimization led to the discovery of compound 33, a highly potent and selective inhibitor of proMMP-9 activation.

Residual Paresthesia After Surgery for Degenerative Cervical Myelopathy: Incidence and Impact on Clinical Outcomes and Satisfaction.

STUDY DESIGN: Multicenter, prospective cohort study. OBJECTIVE: The current study aimed to identify the incidence of residual paresthesias after surgery for degenerative cervical myelopathy (DCM), and to demonstrate the impact of these symptoms on clinical outcomes and patient satisfaction. SUMMARY OF BACKGROUND DATA: Surgery for DCM aims to improve and/or prevent further deterioration of physical function and quality-of-life (QOL) in the setting of DCM. However, patients are often not satisfied with their treatment for myelopathy when they have severe residual paresthesias, even when physical function and QOL are improved after surgery. MATERIALS AND METHODS: The authors included 187 patients who underwent laminoplasty for DCM. All patients were divided into two groups based on their visual analog scale score for paresthesia of the upper extremities at one year postoperatively (>40 vs. ≤40 mm). Preoperative factors, changes in clinical scores and radiographic factors, and satisfaction scales at one year postoperatively were compared between groups. The authors used mixed-effect linear and logistic regression modeling to adjust for confounders. RESULTS: Overall, 86 of 187 patients had severe residual paresthesia at one year postoperatively. Preoperative patient-oriented pain scale scores were significantly associated with postoperative residual paresthesia ( P =0.032). A mixed-effect model demonstrated that patients with severe postoperative residual paresthesia showed significantly smaller improvements in QOL ( P =0.046) and myelopathy ( P =0.037) than patients with no/mild residual paresthesia. Logistic regression analysis identified that residual paresthesia was significantly associated with lower treatment satisfaction, independent of improvements in myelopathy and QOL (adjusted odds ratio: 2.5, P =0.010). CONCLUSION: In total, 45% of patients with DCM demonstrated severe residual paresthesia at one year postoperatively. These patients showed significantly worse treatment satisfaction, even after accounting for improvements in myelopathy and QOL. As such, in patients who experience higher preoperative pain, multidisciplinary approaches for residual paresthesia, including medications for neuropathic pain, might lead to greater clinical satisfaction. LEVEL OF EVIDENCE: 3.

Risk of Revision After Vertebral Augmentation for Osteoporotic Vertebral Fracture: A Narrative Review.

Osteoporotic vertebral fractures (OVFs) can hinder physical motor function, daily activities, and the quality of life in elderly patients when treated conservatively. Vertebral augmentation, which includes vertebroplasty and balloon kyphoplasty, is a commonly used procedure for OVFs. However, there have been reports of complications. Although serious complications are rare, there have been instances of adjacent vertebral fractures, cement dislocation, and insufficient pain relief due to cement failure, sometimes necessitating revision surgery. This narrative review discusses the common risks associated with vertebral augmentation for OVFs, such as cement leakage and adjacent vertebral fractures, and highlights the risk of revision surgery. The pooled incidence of revision surgery was 0.04 (0.02-0.06). The risks for revision are reported as follows: female sex, advanced age, diabetes mellitus, cerebrovascular disease, dementia, blindness or low vision, hypertension, hyperlipidemia, split type fracture, large angular motion, and large endplate deficit. Various treatment strategies exist for OVFs, but they remain a subject of controversy. Current literature underscores the lack of substantial evidence to guide treatment strategies based on the risks of vertebral augmentation. In cases with a high risk of failure, other surgeries and conservative treatments should also be considered as treatment options.

Prediction of Slow-Flow Phenomenon After Stent Implantation Using Near-Infrared Spectroscopy in Patients With Acute and Chronic Coronary Syndrome.

BACKGROUND: The slow-flow phenomenon is associated with worse clinical outcomes after percutaneous coronary intervention (PCI), so our goal for this study was to see how predictive how near-infrared spectroscopy (NIRS) could be.Methods and Results: We enrolled 179 lesions from 152 patients who had de novo coronary stent implantation guided by NIRS-intravascular ultrasound (IVUS) (male: 69.1%, mean age: 74.3±11.5 years, acute coronary syndrome: 65.1%, diabetes: 42.1%). NIRS automatically determined the maximum 4-mm lipid core burden index (maxLCBI4 mm) value at pre- and post-PCI procedures. The slow-flow phenomenon was defined as the deterioration of TIMI (Thrombolysis in Myocardial Infarction) flows on angiography during the PCI procedure in the absence of mechanical obstruction. The slow-flow phenomenon occurred in 13 (7.3%) lesions, and the slow-flow phenomenon group had a significantly higher maxLCBI4 mm(740±147 vs. 471±223, P<0.001). The best maxLCBI4 mmcutoff point in both acute and chronic coronary syndrome was 578 and 480, with sensitivity of 100%, for predicting the slow-flow phenomenon. In the receiver-operating characteristics analysis, the area under the curve for acute and chronic coronary syndrome was 0.849 and 0.851, respectively. CONCLUSIONS: The results of this study support the utility of NIRS-IVUS-guided PCI for the prediction of the slow-flow phenomenon.

Preoperative factors affecting the two-year postoperative patient-reported outcome in single-level lumbar grade I degenerative spondylolisthesis.

Background: The choice of operative method for lumbar spinal stenosis with Meyerding grade I degenerative spondylolisthesis remains controversial. The purpose of this study was to identify the preoperative factors affecting the 2-year postoperative patient-reported outcome in Meyerding grade I degenerative spondylolisthesis. Methods: Seventy-two consecutive patients who had minimally invasive decompression alone (D group; 28) or with fusion (DF group; 44) were enrolled. The parameters investigated were the Japanese Orthopaedic Association back pain evaluation questionnaire as patient-reported assessment, and L4 slippage (L4S), lumbar lordosis (LL), and lumbar axis sacral distance (LASD) as an index of sagittal alignment for radiological evaluation. Data collected prospectively at 2 years postoperatively were examined by statistical analysis. Results: Sixty-two cases (D group; 25, DF group; 37) were finally evaluated. In multiple logistic regression analysis, preoperative L4S and LASD were extracted as significant preoperative factors affecting the 2-year postoperative outcome. Patients with preoperative L4S of 6 mm or more have a lower rate of improvement in lumbar spine dysfunction due to low back pain (risk ratio=0.188, p=.043). Patients with a preoperative LASD of 30 mm or more have a higher rate of improvement in lumbar dysfunction due to low back pain (risk ratio=11.48, p=.021). The results of multiple logistic analysis by operative method showed that there was a higher rate of improvement in lumbar spine dysfunction due to low back pain in patients with preoperative LASD of 30 mm or more in DF group (risk ratio=172.028, p=.01). Conclusions: Preoperative L4S and LASD were extracted as significant preoperative factors affecting patient-reported outcomes at 2 years postoperatively. Multiple logistic analyses by the operative method suggested that DF may be advantageous in improving lumbar dysfunction due to low back pain in patients with preoperative LASD of 30 mm or more.

Factors Predicting the Final Diagnosis in Image-Guided Percutaneous Needle Biopsy for Suspected Spinal Tumors.

In cases of suspected spinal tumors on imaging studies, a biopsy is often necessary for establishing the diagnosis. Predictive factors for tumors or malignancies may help in scheduling biopsies or avoiding unnecessary ones. However, there have been few studies on determining these factors. We aimed to determine the factors associated with the final diagnosis in cases requiring spinal biopsy. This study included 117 patients who underwent image-guided (fluoroscopy- or computed tomography [CT]-guided) needle biopsy of the spine. Data on patient demographic, pathological diagnoses, and final diagnoses were retrospectively collected from the medical records. The imaging features and location of lesions were also evaluated on CT and magnetic resonance imaging. Furthermore, factors related to tumors or malignancies were analyzed. The diagnostic accuracy of biopsy was 94.0%, and there was no difference in the diagnostic accuracy between the fluoroscopic and CT-guided biopsies. Sixty-six and fifty-six patients were diagnosed with spinal tumors and malignant tumors, respectively. Multivariate analysis revealed that a history of malignant tumors and the presence of pedicle lesions and/or extravertebral lesions were related factors for both tumors or malignancy in the final diagnosis. These findings can help determine the necessity for or timing of biopsy in patients with suspected spinal tumors.

Risk Factors for Vulnerable Plaque Detected Using Near-Infrared Spectroscopy in Patients Receiving Statin Therapy with No History of Coronary Artery Disease.

Residual risk of atherosclerosis remains high despite the use of lipid-lowering therapy with statins. Near-infrared spectroscopy intravascular ultrasound imaging (NIRS-IVUS) can identify vulnerable plaque via the detection of lipid-rich plaque. This study aimed to reveal the clinical characteristics of patients with vulnerable plaque despite statin therapy.NIRS-IVUS was used to determine the maximum 4 mm Lipid Core Burden Index (MaxLCBI4 mm) values of 38 de novo culprit lesions from 32 patients with acute coronary syndrome (53%) (mean age: 73.1 ± 13.1 years) who underwent percutaneous coronary intervention after a minimum 6 months of statin therapy for primary prevention. A patient with vulnerable plaque was defined as an individual presenting at least 1 target lesion with a vulnerable plaque (MaxLCBI4 mm > 400). Overall, the average low-density lipoprotein cholesterol (LDL-C) level was 95.5 ± 27.2 mg/dL. Patients in the vulnerable plaque group were younger and had higher LDL-C, triglycerides, and non-high-density lipoprotein cholesterol (HDL-C) levels than those in the non-vulnerable plaque group. The MaxLCBI4 mm was positively correlated with LDL-C (P = 0.0002), triglycerides (P = 0.0003), and non-HDL-C (P = 0.0001). In multivariate analysis, all 3 treatable lipid components failed to show an independent relationship with the patients with vulnerable plaque. Using receiver-operating characteristics curve analysis, the cutoff points for LDL-C, triglycerides, and non-HDL-C were determined to be 78 mg/dL, 108 mg/dL, and 111 mg/dL, respectively, at MaxLCBI4 mm > 400. In conclusion, this study supports a more comprehensive and aggressive lipid-lowering therapy for the primary prevention of coronary artery disease.

Muscle strength rather than appendicular skeletal muscle mass might affect spinal sagittal alignment, low back pain, and health-related quality of life.

Sarcopenia is defined as decreasing in muscle strength and mass, and dynapenia is defined as decreasing in muscle strength and maintained muscle mass. This study elucidated the prevalence and characteristics of sarcopenia and dynapenia and evaluate in elderly spinal disorders patients. 1039 spinal disorders patients aged ≥ 65 years were included. We measured age, grip strength, muscle mass, spinal sagittal alignment parameters, low back pain (LBP) scores and health-related quality of life (HR-QoL) scores. Based on the previous reports, patients were categorised into normal group: NG, pre-sarcopenia group: PG, dynapenia group: DG, and sarcopenia group: SG. Pre-sarcopenia, dynapenia, and sarcopenia were found in 101 (9.7%), 249 (19.2%), and 91 (8.8%) patients, respectively. The spinal sagittal alignment parameters, trunk muscle mass, LBP, and HR-QoL scores were significantly worse in DG and SG compared with those in PG and NG. Spinal alignment, trunk muscle mass, and clinical outcomes, including LBP and HR-QoL scores, were maintained in the PG and poor in the DG and SG. Thus, intervention for muscle strength may be a treatment option for changes of spinal sagittal alignment and low back pain.

Risk Factors for Poor Outcome after Palliative Surgery for Metastatic Spinal Tumors.

Palliative surgery is performed to improve the quality of life of patients with spinal metastases. However, it is sometimes difficult to achieve the expected results because the patient's condition, and risk factors related to poor outcomes have not been well elucidated. This study aimed to evaluate the functional outcomes and investigate the risk factors for poor outcomes after palliative surgery for spinal metastasis. We retrospectively reviewed the records of 117 consecutive patients who underwent palliative surgery for spinal metastases. Neurological and ambulatory statuses were evaluated pre- and post-operatively. Poor outcomes were defined as no improvement or deterioration in functional status or early mortality, and the related risk factors were analyzed using multivariate logistic regression analysis. The results showed neurological improvement in 48% and ambulatory improvement in 70% of the patients with preoperative impairment, whereas 18% of the patients showed poor outcomes. In the multivariate analysis, low hemoglobin levels and low revised Tokuhashi scores were identified as risk factors for poor outcomes. The present results suggest that anemia and low revised Tokuhashi scores are related not only to life expectancy but also to functional recovery after surgery. Treatment options should be carefully selected for the patients with these factors.

Analyses of associated factors with concomitant meniscal injury and irreparable meniscal tear at primary anterior cruciate ligament reconstruction in young patients.

Purpose: Although several factors related to the concomitant meniscal injury at anterior cruciate ligament reconstruction (ACL-R) have been investigated in a general population, few studies have identified the risk factors of meniscal tear severity in young patients in which the majority of ACL tears occur. The purpose of this study was to analyze the associated factors with meniscal injury and irreparable meniscal tear and the timeline for medial meniscal injury at ACL-R in young patients. Methods: A retrospective analysis of young patients (13 to 29 years of age) who underwent ACL-R by a single surgeon from 2005 to 2017 was conducted. Predictor variables (age, sex,body mass index [BMI], time from injury to surgery [TS], and pre-injury Tegner activity level) for meniscal injury and irreparable meniscal tear were analyzed with multivariate logistic. Results: Four hundred and seventy-three consecutive patients with an average of 31.2 months post-operative follow-up were enrolled in this study. The risk factors for medial meniscus injury were TS (<= 3 months) (odds ratio [OR], 3.915; 95% CI, 2.630-5.827; P < .0001) and higher BMI (OR, 1.062; 95% CI, 1.002-1.125; P = 0.0439). The presence of irreparable medial meniscal tears correlated with higher BMI (OR, 1.104; 95% CI, 1.011-1.205; P = 0.0281). Conclusion: An increased time from ACL tear to surgery of 3 months was strongly associated with an increased risk of medial meniscus injury, but not related to irreparable medial meniscal tear at primary ACL reconstruction in young patients. Level of Evidence: Level IV.