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1.
Sensors (Basel) ; 24(11)2024 May 23.
Article in English | MEDLINE | ID: mdl-38894125

ABSTRACT

With the introduction of deep learning, a significant amount of research has been conducted in the field of computer vision in the past decade. In particular, research on object detection (OD) continues to progress rapidly. However, despite these advances, some limitations need to be overcome to enable real-world applications of deep learning-based OD models. One such limitation is inaccurate OD when image quality is poor or a target object is small. The performance degradation phenomenon for small objects is similar to the fundamental limitations of an OD model, such as the constraint of the receptive field, which is a difficult problem to solve using only an OD model. Therefore, OD performance can be hindered by low image quality or small target objects. To address this issue, this study investigates the compatibility of super-resolution (SR) and OD techniques to improve detection, particularly for small objects. We analyze the combination of SR and OD models, classifying them based on architectural characteristics. The experimental results show a substantial improvement when integrating OD detectors with SR models. Overall, it was demonstrated that, when the evaluation metrics (PSNR, SSIM) of the SR models are high, the performance in OD is correspondingly high as well. Especially, evaluations on the MS COCO dataset reveal that the enhancement rate for small objects is 9.4% higher compared to all objects. This work provides an analysis of SR and OD model compatibility, demonstrating the potential benefits of their synergistic combination. The experimental code can be found on our GitHub repository.

2.
Microorganisms ; 12(4)2024 Apr 11.
Article in English | MEDLINE | ID: mdl-38674720

ABSTRACT

Probiotics should possess specific properties to exert beneficial effects, and their safety must be ensured for human consumption. The purpose of this study was to evaluate the probiotic properties and safety of Limosilactobacillus mucosae NK41 and Bifidobacterium longum NK46 isolated from human feces in vitro. Both strains exhibited high resistance to simulated gastrointestinal fluid. Furthermore, probiotic-related cell surface characteristics including auto-aggregation and cell surface hydrophobicity were assessed by measuring the absorbance at a wavelength of 600 nm, which demonstrated good auto-aggregation ability and affinity for xylene, indicating their effective adhesion to Caco-2 cells. In addition, hemolytic, gelatinase, and ß-glucuronidase activities were found to be negative in both strains. The susceptibility to nine commonly used antibiotics was assessed using the broth macrodilution method, which demonstrated that both strains were susceptible to all tested antibiotics. Furthermore, L. mucosae NK41 and B. longum NK46 produced significantly higher levels of L-lactate (71.8 ± 0.7% and 97.8 ± 0.4%) than D-lactate (28.2 ± 0.7% and 2.2 ± 0.4%, respectively). Using PCR amplification to investigate genes associated with virulence factors, we found that neither strain harbored any virulence genes. These findings suggest that L. mucosae NK41 and B. longum NK46 have the potential to be used as probiotics and are considered safe for human consumption.

3.
J Neurosurg Spine ; 40(2): 132-142, 2024 Feb 01.
Article in English | MEDLINE | ID: mdl-38000072

ABSTRACT

OBJECTIVE: Lumbar degenerative kyphosis (LDK), a flexible deformity, is a common form of sagittal imbalance in Asian countries. Assessing a patient's spine prior to surgery by using positional radiographs is becoming more crucial in determining surgical planning to achieve favorable clinical and radiographic outcomes, especially in patients with flexible deformities. This study aims to identify radiographic characteristics of supine pelvic tilt (sPT) and its relation to mechanical failure (MF) following LDK correction. METHODS: A single-center, single-surgeon retrospective analysis was performed in patients who underwent LDK correction with sacropelvic fixation between January 2014 and May 2019. Patients were grouped into pelvic match and mismatch groups according to the difference between postoperative pelvic tilt (PT) and sPT. Demographic, surgical, and radiographic parameters were compared. Chronological change of PT was assessed by comparing preoperative, supine, immediate postoperative, and final PT. RESULTS: Baseline demographics and sagittal alignments were similar between PT match (n = 25) and mismatch (n = 42) groups (p > 0.05). There was a significant difference in the rate of MF between PT match and mismatch groups (4% vs 31%, p = 0.021). Multivariable analysis demonstrated that after including control variables, PT mismatch was independently associated with the likelihood of MF development (OR 33.42, p = 0.04). CONCLUSIONS: sPT reflects postoperative PT changes; therefore, supine imaging may represent a tool that could be used for preoperative decision-making in patients with LDK or possibly those with flexible adult spinal deformity. PT mismatch > 10° or < 0° is a significant risk factor for MF following correction of LDK. Measurement of sPT would aid surgeons in optimal preoperative planning and in minimizing catastrophic MF following deformity correction surgery.


Subject(s)
Kyphosis , Scoliosis , Adult , Humans , Retrospective Studies , Kyphosis/diagnostic imaging , Kyphosis/surgery , Spine/surgery , Pelvis/diagnostic imaging , Pelvis/surgery , Lumbar Vertebrae/diagnostic imaging , Lumbar Vertebrae/surgery
4.
Oper Neurosurg (Hagerstown) ; 26(3): 268-278, 2024 Mar 01.
Article in English | MEDLINE | ID: mdl-37856767

ABSTRACT

BACKGROUND AND OBJECTIVES: Proximal junctional kyphosis/failure (PJK/F) is a potentially serious complication after adult spinal deformity (ASD) corrective surgery. Recurrent PJK/F is especially troublesome, necessitating fusion extension and occasionally resulting in irreversible neurological deficits. The gravity line (GL) offers valuable insights into global sagittal balance. This study aims to examine the postoperative GL-hip axis (GL-HA) offset as a critical risk factor for recurrent PJK/F. METHODS: We retrospectively reviewed patients with ASD who had undergone revision surgery for initial PJK/F at a single academic center. Patients were categorized into 2 groups: nonrecurrent PJK/F group and recurrent PJK/F group. Demographics, surgical characteristics, preoperative and postoperative parameters of spinopelvic and global alignment, and the Scoliosis Research Society-22 scores were assessed. We examined these measures for differences and correlations with recurrent PJK/F. RESULTS: Our study included 32 patients without recurrent PJK/F and 28 patients with recurrent PJK/F. No significant differences were observed in baseline demographics, operative characteristics, or Scoliosis Research Society-22 scores before and after surgery. Importantly, using a cutoff of -52.6 mm from logistic regression, there were considerable differences and correlations with recurrent PJK/F in the postoperative GL-HA offset, leading to an odds ratio of 7.0 (95% CI: 1.94-25.25, P = .003). CONCLUSION: Postoperative GL-HA offset serves as a considerable risk factor for recurrent PJK/F in patients with ASD who have undergone revision surgery. Overcorrection, with GL-HA offset less than -5 cm, is associated with recurrent PJK/F. The instrumented spine tends to align the GL near the HA, even at the cost of proximal junction.


Subject(s)
Kyphosis , Scoliosis , Adult , Humans , Scoliosis/diagnostic imaging , Scoliosis/surgery , Retrospective Studies , Kyphosis/prevention & control , Kyphosis/surgery , Kyphosis/etiology , Spine/surgery , Risk Factors
5.
J Korean Neurosurg Soc ; 67(2): 137-145, 2024 Mar.
Article in English | MEDLINE | ID: mdl-37752818

ABSTRACT

In adult spinal deformity (ASD) surgery, mechanical failure (MF) has been a significant concern for spine surgeons as well as patients. Despite earnest endeavors to prevent MF, the absence of a definitive consensus persists, owing to the intricate interplay of multifarious factors associated with this complication. Previous approaches centered around global spinal alignment have yielded limited success in entirely forestalling MF. These methodologies, albeit valuable, exhibited limitations by neglecting to encompass global balance and compensatory mechanisms within their purview. In response to this concern, an in-depth comprehension of global balance and compensatory mechanisms emerges as imperative. In this discourse, the center of gravity and the gravity line are gaining attention in recent investigations pertaining to global balance. This narrative review aims to provide an overview of the global balance and a comprehensive understanding of related concepts and knowledge. Moreover, it delves into the clinical ramifications of the contemporary optimal correction paradigm to furnish an encompassing understanding of global balance and the current optimal correction strategies within the context of ASD surgery. By doing so, it endeavors to furnish spine surgeons with a guiding compass, enriching their decision-making process as they navigate the intricate terrain of ASD surgical interventions.

6.
Neurospine ; 20(3): 799-807, 2023 Sep.
Article in English | MEDLINE | ID: mdl-37798973

ABSTRACT

Adolescent idiopathic scoliosis (AIS) affects approximately 2% of adolescents across all ethnicities. The objectives of surgery for AIS are to halt curve progression, correct the deformity in 3 dimensions, and preserve as many mobile spinal segments as possible, avoiding junctional complications. Despite ongoing development in algorithms and classification systems for the surgical treatment of AIS, there is still considerable debate about selecting the appropriate fusion level. In this study, we review the literature on fusion selection and present current concepts regarding the lower instrumented vertebra in the selection of the fusion level for AIS surgery.

7.
Neurospine ; 20(3): 981-988, 2023 Sep.
Article in English | MEDLINE | ID: mdl-37798992

ABSTRACT

OBJECTIVE: Multilevel or revisional posterior spinal surgery is prone to infection and delayed wound healing, related with the wound closure time and suture strength. Knotless barbed suture is an innovative self-locking, multianchor suture. This study aims to evaluate the safety and efficacy of the knotless barbed suture and self-adhering mesh with polymeric glue in multilevel or revisional posterior spinal surgery. METHODS: This is a single-center retrospective matched cohort study. Patients were divided into 2 groups based on the wound closure method: barbed suture group with novel wound closure, and conventional suture group with conventional wound closure, 1:1 matched by the level of surgery and sex, resulting in 120 subjects each. Total operation time and wound closure time were measured intraoperatively, and perioperative clinical outcome parameters including postoperative wound complication were investigated for the first 3 months postoperatively. The distribution of continuous variables was assessed for normality by Shapiro-Wilk test, then parametric or nonparametric tests were applied accordingly (paired t-test or Wilcoxon signed-rank test). RESULTS: Wound closure time was significantly shorter with the novel barbed suture than with conventional suture in all subgroups divided by the level of spinal surgery: 3-5, 6-9, ≥ 10 levels (p < 0.001). The 2 groups showed no significant differences in surgical complications (p = 1.000). Specially, total operation time and wound-closing time were significantly shorter in revisional subgroup. CONCLUSION: Absorbable knotless barbed suture and self-adhering mesh with polymeric glue can shorten spinal wound closure time with noninferiority in complications for multilevel or revisional spinal surgery.

9.
Neurosurgery ; 92(5): 998-1005, 2023 05 01.
Article in English | MEDLINE | ID: mdl-36700742

ABSTRACT

BACKGROUND: Mechanical failure (MF) is a serious burden for patients with adult spinal deformity (ASD) who have undergone deformity correction surgery. Surgeons have sought to understand the mechanism and prevent this problematic complication, but this goal remains to be achieved. The gravity line (GL) of the whole body is a noteworthy parameter that represents global sagittal balance, for which normative values for the axial skeleton have been studied. OBJECTIVE: To assess postoperative GL-hip axis (GL-HA) offset as a critical risk factor for MF after ASD correction surgery. METHODS: Consecutive patients who underwent initial surgery for ASD at a single academic center were retrospectively included. Demographics, operative details, preoperative and postoperative spinopelvic parameters, global sagittal balance parameters, and Scoliosis Research Society-22 score were evaluated. These variables were analyzed for differences and correlations with MF. RESULTS: Thirty-five patients without MF and 30 patients with MF were identified in the study. Two groups showed no significant differences in baseline demographics, operative characteristics, preoperative global sagittal balance parameters, or preoperative and postoperative Scoliosis Research Society-22 scores. Significant differences and correlations with MF were observed for postoperative GL-HA offset using a cutoff value of 49.3 mm from logistic regression analysis, with an odds ratio of 11.0 (95% confidence interval: 3.45-35.01, P < .0001). CONCLUSION: Postoperative GL-HA offset is a substantial risk factor for MF after ASD surgery. Surgical correction of ASD with a GL-HA offset greater than 5 cm is significantly related to MF. The GL should be located near the HA after ASD surgery.


Subject(s)
Scoliosis , Spinal Fusion , Humans , Adult , Scoliosis/surgery , Retrospective Studies , Gravitation , Postoperative Period , Risk Factors , Spinal Fusion/adverse effects
10.
Neurospine ; 20(4): 1246-1255, 2023 Dec.
Article in English | MEDLINE | ID: mdl-38171292

ABSTRACT

Cervical spinal deformity (CSD) is a complex condition characterized by abnormal curvature and cervical spine alignment. It can lead to a multitude of symptoms, including chronic pain, neurological deficits, and functional impairments, severely impacting an individual's health-related quality of life (HRQoL). Surgical intervention is often necessary to address the deformity and alleviate symptoms, but optimal surgical strategies remain a topic of ongoing research and debate. This narrative review aims to provide an in-depth overview of the surgical management of CSD, focusing on optimizing patient outcomes and enhancing readers' understanding of the complexities involved. We begin by discussing the importance of preoperative assessment, including comprehensive radiographic evaluation and careful consideration of the global spinal alignment. The relationship between the cervical spine and the reciprocal changes that occur are explored to guide surgeons in their decision-making process. Furthermore, we delve into the selection of fusion levels, emphasizing the significance of identifying the primary driver of deformity. We review the current literature on optimal alignment targets and strategies to optimize surgical planning. By providing a comprehensive analysis of the surgical management of CSD, this review aims to enhance the readers' knowledge and assist surgeons in making informed decisions when planning and executing surgical interventions. Understanding the intricacies of CSD correction and the latest advancements in the field can ultimately improve patient outcomes and enhance HRQoL for individuals suffering from this challenging condition.

11.
Microorganisms ; 10(11)2022 Nov 13.
Article in English | MEDLINE | ID: mdl-36422317

ABSTRACT

Lactic acid bacteria (LAB) can improve host health and has strong potential for use as a health functional food. Specific strains of LAB have been reported to exert immunostimulatory effects. The primary goal of this study was to evaluate the immunostimulatory activities of novel LAB strains isolated from humans and foods and to investigate the probiotic properties of these strains. Cell-free supernatants (CFS) obtained from selected LAB strains significantly increased phagocytosis and level of nitric oxide (NO) and pro-inflammatory cytokines such as tumor necrosis factor (TNF)-α and interleukin (IL)-6 in RAW264.7 macrophage cells. The protein expression of inducible NO synthase (iNOS) and cyclooxygenase (COX)-2, which are immunomodulators, was also upregulated by CFS treatment. CFS markedly induced the phosphorylation of nuclear factor-κB (NF-κB) and MAPKs (ERK, JNK, and p38). In addition, the safety of the LAB strains used in this study was demonstrated by hemolysis and antibiotic resistance tests. Their stability was confirmed under simulated gastrointestinal conditions. Taken together, these results indicate that the LAB strains selected in this study could be useful as probiotic candidates with immune-stimulating activity.

12.
Neurospine ; 19(2): 463-471, 2022 Jun.
Article in English | MEDLINE | ID: mdl-35793937

ABSTRACT

OBJECTIVE: By using angulation of the axis itself, this study aims to define and analyze odontoid incidence (OI) and odontoid tilt (OT) as novel cervical alignment parameters and investigate their correlations with cervical alignment. METHODS: Novel and existing parameters were measured with whole-spine lateral plain radiographs and EOS images of 42 adults without cervical symptoms. The correlations of OI, OT, C2 slope (C2S), and T1 slope (T1S) were calculated. RESULTS: The OI, OT, and C2S showed significant correlations with C2-7 angle (r = 0.43, r = -0.42, r = 0.62, respectively) and C0-2 angle (r = -0.33, r = 0.48, r = -0.61, respectively). OI, OT, T1S were independent predictors of the C2-7 angle in univariate regression analysis (adjusted-R2 = 0.17, R2 = 0.15, R2 = 0.28, respectively). OI, OT, and T1S were independent predictors in the multivariable regression analysis with estimated standardized coefficients of 0.36, -0.67, -0.69, respectively (adjusted- R2 = 0.80, p < 0.001). Regarding the C0-2 angle, OI and OT were independent predictors in the univariate regression analysis (adjusted-R2 = 0.08, R2 = 0.21, respectively). CONCLUSION: OI, OT, and C2S had significant correlations with cervical alignment. As the pelvic incidence, the OI is the only anatomical and constant parameter that could be used as a reference point related to the cervical spine from the rostral end. The study results may serve as baseline data for further studies on the alignment and balance of the cervical spine.

13.
Asian Spine J ; 16(6): 958-967, 2022 Dec.
Article in English | MEDLINE | ID: mdl-35527534

ABSTRACT

The idea of the global balance of spine stems from Jean Dubousset, who first introduced the concept of cone of economy. Through the compensatory mechanisms, the human body maintains an upright posture and horizontal gaze in the setting of the spinal malalignment. Compensation takes place not only in the mobile spine segments, but also in the pelvis and lower extremities. Patients with a malalignment exhibit compensatory changes in the cervical hyper-lordosis, posterior pelvic shift, knee/ankle flexion, hip extension, and the pelvic retroversion. The advent of whole-body stereo radiography has yielded an improved understanding of global changes among the patients. Deformity-induced compensatory changes in the sagittal alignment could be resolved reciprocally after the surgical correction of the malalignment. Thoracolumbar realignment surgery restores the pathologic compensatory changes in the unfused spinal segments, pelvis, and the lower extremities. Similarly, reciprocal changes in the thoracolumbar spine may harmonize global sagittal alignment after the cervical reconstruction. This study reviews the compensatory mechanisms and reciprocal changes in global sagittal alignment caused by the surgical correction and highlights, the factors that should be considered while assessing a patient's compensatory status.

14.
J Neurosurg Spine ; : 1-8, 2022 Jan 21.
Article in English | MEDLINE | ID: mdl-35061993

ABSTRACT

OBJECTIVE: Magnetic resonance imaging (MRI) is the gold-standard tool for diagnosing lumbar spinal stenosis (LSS), but it is difficult to promptly examine all suspected cases with MRI considering the modality's high cost and limited accessibility. Although radiography is an efficient screening technique owing to its low cost, rapid operability, and wide availability, its diagnostic accuracy is relatively poor. In this study, the authors aimed to develop a deep learning model with a convolutional neural network (CNN) for diagnosing severe central LSS using radiography and to evaluate radiological diagnostic features using gradient-weighted class activation mapping (Grad-CAM). METHODS: Patients who had undergone both spinal MRI and radiography in the period from May 1, 2005, to December 31, 2017, were screened. According to the formal MRI report, participants were consecutively included in the severe central LSS or healthy control group, and radiographs for both groups were collected. A CNN-based transfer learning algorithm was developed to classify radiographic findings as LSS or normal (binary classification). The proposed models were evaluated using six performance metrics: area under the receiver operating characteristic curve (AUROC), accuracy, sensitivity, specificity, and positive and negative predictive values. RESULTS: The VGG19 model achieved the highest accuracy with an AUROC of 90.0% (95% CI 89.8%-90.3%) by training 12,442 images. Accuracy was 82.8% (95% CI 82.5%-83.1%) by averaging 5-fold models. Feature points on Grad-CAM were reasonable, and the features could be categorized into reduced disc height, narrow foramina, short pedicle, and hyperdense facet joint. The AUROC in the extra validation was 89.3% (95% CI 88.7%-90.0%). Accuracy was 81.8% (95% CI 80.6%-83.0%) by averaging 5-fold models. Multivariate logistic regression analysis showed that a combination of demographic factors (age and sex) did not improve the model performance. CONCLUSIONS: The algorithm trained by a CNN to identify central LSS on radiographs showed high diagnostic accuracy and is expected to be useful as a triage tool. The algorithm could accurately localize the stenotic lesion to assist physicians in the identification of LSS.

15.
Neurospine ; 19(4): 853-861, 2022 Dec.
Article in English | MEDLINE | ID: mdl-36597620

ABSTRACT

Over the last few decades, the importance of the sagittal plane and its contour has gained significant recognition. Through full-body stereoradiography, the understanding of compensatory mechanisms, and the concept of global balance and reciprocal change has expanded. There have been a few reports describing how cervical realignment surgery affects global spinal alignment (GSA) and global balance. Despite the research efforts, the concept of reciprocal change and global balance is still perplexing. Understanding the compensatory status and main drivers of deformity in a patient is vital because the compensatory mechanisms may resolve reciprocally following cervical realignment surgery. A meticulous preoperative evaluation of the whole-body alignment, including the pelvis and lower extremities, is paramount to appreciate optimal GSA in the correction of spinal malalignment. This study aims to summarize relevant literature on the reciprocal changes in the whole body caused by cervical realignment surgery and review recent perspectives regarding cervical compensatory mechanisms.

16.
Neurospine ; 19(4): 912-920, 2022 Dec.
Article in English | MEDLINE | ID: mdl-36597628

ABSTRACT

OBJECTIVE: C2 slope (C2S), a cervical parameter mathematically approximated as T1 slope minus cervical lordosis (T1S-CL), predicts functional improvement in cervical deformity patients. Nonetheless, C2S is a positional parameter based only on the horizontal axis. The current study aims to introduce novel odontoid parameters and establish their relationships with patient-reported health-related quality of life (HRQoL). METHODS: Lateral plain radiographs of 32 adults who underwent multilevel posterior cervical fusion were analyzed. The odontoid parameters included odontoid incidence (OI), C2S, odontoid tilt (OT), and gravity line-C2 distance (GL-C2), while the cervical parameters were the Cobb angle at C0-1, C1-2, C0-2, C2-7, C2-7 sagittal vertical axis (cSVA), T1 slope, and T1S-CL. The range of motion (ROM) of the occipito-atlantoaxial complex was measured in flexion and extension plain radiographs. Scores on the Neck Disability Index (NDI) and visual analogue scale (VAS) for axial neck (VASn) and arm pain were measured. RESULTS: Compared to asymptomatic subjects, patients had larger C2S, cSVA, and T1S-CL, and smaller OT. Preoperatively, OI was significantly correlated with the ROM of C1-2 (r = 0.37, p < 0.05) and C0-2 (r = 0.46, p < 0.01). OT and C2S had significant correlations with the C0-1, C1-2, and C0-2 angles, GL-C2, and T1S-CL. Postoperative NDI scores were significantly correlated with OI (r = -0.40, p < 0.05) and OT (ρ = -0.37, p < 0.05). VASn was significantly correlated with GL-C2 (r = -0.35, p < 0.05). CONCLUSION: The odontoid parameters were significantly correlated with established cervical parameters and HRQoL measures. OI is a constant parameter representing the individual's compensatory reservoir at the upper cervical spine.

17.
Sensors (Basel) ; 21(5)2021 Mar 09.
Article in English | MEDLINE | ID: mdl-33803175

ABSTRACT

Recently, researchers have paid attention to many types of huge networks such as the Internet of Things, sensor networks, social networks, and traffic networks because of their untapped potential for theoretical and practical outcomes. A major obstacle in studying large-scale networks is that their size tends to increase exponentially. In addition, access to large network databases is limited for security or physical connection reasons. In this paper, we propose a novel sampling method that works effectively for large-scale networks. The proposed approach makes multiple heterogeneous Markov chains by adjusting random-walk traits on the given network to explore the target space efficiently. This approach provides better unbiased sampling results with reduced asymptotic variance within reasonable execution time than previous random-walk-based sampling approaches. We perform various experiments on large networks databases obtained from synthesis to real-world applications. The results demonstrate that the proposed method outperforms existing network sampling methods.

18.
Neurospine ; 18(4): 733-740, 2021 Dec.
Article in English | MEDLINE | ID: mdl-35000326

ABSTRACT

This paper is an overview of various features of regional anesthesia (RA) and aims to introduce spine surgeons unfamiliar with RA. RA is commonly used for procedures that involve the lower extremities, perineum, pelvic girdle, or lower abdomen. However, general anesthesia (GA) is preferred and most commonly used for lumbar spine surgery. Spinal anesthesia (SA) and epidural anesthesia (EA) are the most commonly used RA methods, and a combined method of SA and EA (CSE). Compared to GA, RA offers numerous benefits including reduced intraoperative blood loss, arterial and venous thrombosis, pulmonary embolism, perioperative cardiac ischemic incidents, renal failure, hypoxic episodes in the postanesthetic care unit, postoperative morbidity and mortality, and decreased incidence of cognitive dysfunction. In spine surgery, RA is associated with lower pain scores, postoperative nausea and vomiting, positioning injuries, shorter anesthesia time, and higher patient satisfaction. Currently, RA is mostly used in short lumbar spine surgeries. However, recent findings illustrate the possibility of applying RA in spinal tumors and spinal fusion. Various researches reveal that SA is an effective alternative to GA with lower minor complications incidence. Comprehensive insight on RA will promote spine surgery under RA, thereby broadening the horizon of spine surgery under RA.

19.
Stress ; 23(2): 153-161, 2020 03.
Article in English | MEDLINE | ID: mdl-31469025

ABSTRACT

Successful shooting performance in competition is reliant on several factors such as shooting techniques and competition-associated psychological stresses. This study examined the hypothalamus-pituitary-adrenal (HPA) axis response to upcoming competition and its association with shooting outcomes in elite junior shooting players. The cortisol awakening response (CAR) and dehydroepiandrosterone (DHEA) secretion after awakening were measured for two consecutive days (the day before and on the day of competition for the selection of national shooting team members) in 19 junior men and 21 junior women players, and the shooting scores of the individual players were obtained. The total cortisol secretion during the CAR period (CARauc) increased, but total DHEA secretion during the post-awakening period (Daucawk) decreased on the day of competition, compared with one day before competition. The CARauc was higher in women than in men players, whereas Daucawk was higher in men than in women players across the two consecutive days. Cortisol and DHEA levels were comparable between low-scored (below the mean scores for air pistol or air rifle players) and high-scored players one day before competition. However, the CARauc on the day of competition was higher and the variations in the CARauc and molar CARauc/Daucawk ratios across the two consecutive days were greater in low-scored than in high-scored men and women players. These results indicated that upcoming competition involves alterations of the CAR and DHEA secretion after the awakening period, and greater HPA response to the upcoming competition was adversely associated with shooting scores in junior shooting athletes.Lay summaryAn important upcoming competition was perceived as a strong stressor on awakening that induced alteration in CAR and DHEA secretion after the awakening period in elite shooting players. This study observed that, irrespective of their age and period of shooting practice, the HPA axis function on the day of competition was associated with shooting outcomes in elite shooting players.


Subject(s)
Hypothalamo-Hypophyseal System , Pituitary-Adrenal System , Circadian Rhythm , Female , Humans , Hydrocortisone , Male , Saliva , Stress, Psychological
20.
Br J Sports Med ; 49(17): 1144-50, 2015 Sep.
Article in English | MEDLINE | ID: mdl-26216871

ABSTRACT

PURPOSE: To present an epidemiological study of injuries found among South Korea's National level Judo athletes as a foundation for future injury prevention and skill enhancement in this group. METHODS: This study is a prospective study on a 4-year injury assessment held from January 2010 to December 2013 at the training centre in South Korea for National Level athletes. Athlete's weight class, gender, injury location and injury grade (grade I=1-3 treatment days, grade II=4-7 treatment days, and grade III ≥8 treatment days) were analysed. RESULTS: There were a total of 782 injuries recorded during this period, equalling to four injuries per athlete annually. Almost half of these injuries (47%) were grade I injuries. Injury occurrence was the highest in the Lower body (44.2%). This was then followed by injuries in the upper body (29.8%), trunk (20.3%) and head and neck (5.6%). Men and women showed similar, non-significantly different trends in the proportion of body parts injured. Women experienced more grade III injuries than males (p=0.0228). Comparison between women in different weight classes also showed that heavyweights incurred more grade III injuries than lightweights (p=0.0087). Lightweights had a higher rate of injury than heavyweights in males and females, although this was statistically significant only among males (p<0.001). CONCLUSIONS: Many body regions are prone to injury in the elite judo population. Women, especially those in the heavyweight classification, were more prone to severe injuries. Lightweights experienced more injuries than heavyweights among male athletes. Specifically, further studies are needed to confirm these findings and to address the impact of rapid weight loss practices on injury risk to implement effective preventive measures.


Subject(s)
Martial Arts/injuries , Age Distribution , Athletic Injuries/epidemiology , Female , Humans , Male , Musculoskeletal System/injuries , Prospective Studies , Republic of Korea/epidemiology
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