• Archives of Hand and Microsurgery
• /
• v.23 no.4
• /
• pp.254-261
• /
• 2018

Purpose: Favorable results have been reported after the direct repair of chronic ulnar collateral ligament ruptures of the thumb metacarpophalangeal (MP) joint, but the results for radial ligament seem rather controversial. The purpose of this study is to compare the results of ligament reattachment between chronic rupture of the ulnar and the radial collateral ligament (RCL) of the joint. Methods: We reviewed retrospectively the radiologic and clinical results of ligament reattachment with suture anchors for chronic (more than 6 weeks) rupture of the collateral ligament of the thumb MP joint with averaged 22-month follow-up. The data between 6 radial and 8 ulnar ligament repairs were compared statistically. Results: The average of postoperative ulnar deviation angle was $13.3^{\circ}$ in radial ligament and $2.0^{\circ}$ in ulnar ligament (p=0.020) in the last follow-up plain X-ray. Postoperative ligament instability was positive in 4 out of the 6 radial repairs and no case with instability was observed in ulnar ligament. In postoperative follow-up, sustained joint subluxation was observed only in 2 out of the 6 radial repairs. Conclusion: The delayed repair of the RCL of the thumb MP joint resulted in less favorable outcomes and ligament instability was observed postoperatively in more than half of the cases.

• Nuclear Engineering and Technology
• /
• v.51 no.5
• /
• pp.1241-1250
• /
• 2019

This study mainly focused on the neutronics modeling of bubbles in bubbly flow in boiling water reactors. The bubble, ring and homogenous models were used for radial void fraction distribution. Effect of the bubble and ring models on the infinite multiplication factor and two-group flux distribution was investigated by comparing with the homogenous model. Square pitch unit cell geometry was used in the calculations. In the bubble model, spherical and non-spherical bubbles at random positions, sizes and shapes were produced by Monte Carlo method. The results show that there are significant differences among the proposed models from the viewpoint of physical interaction mechanism. For the fully-developed bubbly flow, $k_{inf}$ is overestimated in the ring model by about $720{\pm}6pcm$ with respect to homogeneous model whereas underestimated in the bubble model by about $-65{\pm}9pcm$ with a standard deviation of 15 pcm. In addition, the ring model shows that the coolant must be separated into regions to properly represent the radial void distribution. Deviations in flux distributions principally occur in certain regions, such as corners. As a result, the bubble model in modeling the void fraction can be used in nuclear engineering calculations.

• Current Optics and Photonics
• /
• v.3 no.5
• /
• pp.466-472
• /
• 2019

A system for continuous-wave coherent Doppler lidar (CW lidar), made up of all-fiber structures and a coaxial transmission telescope, was set up for wind measurement in Hefei (31.84 N, 117.27 E), Anhui province of China. The lidar uses a fiber laser as a light source at a wavelength of $1.55{\mu}m$, and focuses the laser beam on a location 80 m away from the telescope. Using the CW lidar, radial wind measurement was carried out. Subsequently, the spectra of the atmospheric backscattered signal were analyzed. We tested the noise and obtained the lower limit of wind velocity as 0.721 m/s, through the Rayleigh criterion. According to the number of Doppler peaks in the radial wind spectrum, a classification retrieval algorithm (CRA) combining a Gaussian fitting algorithm and a spectral centroid algorithm is designed to estimate wind velocity. Compared to calibrated pulsed coherent wind lidar, the correlation coefficient for the wind velocity is 0.979, with a standard deviation of 0.103 m/s. The results show that CW lidar offers satisfactory performance and the potential for application in wind measurement.

• Archives of Reconstructive Microsurgery
• /
• v.21 no.2
• /
• pp.86-91
• /
• 2012

Purpose: Mass can compress around tissue and cause deviation of normal anatomical structures. Often, mass grows toward neurovascular pedicle and encircles depending on the nature of mature mass. Neglecting neurovascular involvement of the mass is a serious problem not to be overlooked. Authors have performed microscopic approach regarding mass involving the neurovascular pedicle in the hand. Materials and Methods: From January 2007 through February 2012, retrospective analysis for nine cases of mass involving neurovascular pedicles was done. Patients were evaluated preoperatively by ultrasonography or MRI and checked intraoperative finding. Masses were evaluated by site, preoperative evaluation, involved neurovascular pedicle, histopathologic diagnosis, complication, and recurrence. Results: The site of mass involving neurovascular pedicles was 4 cases on the wrist, 2 cases on the palm, 2 cases on the finger, 1 case on the hand dorsum. Involved neurovascular pedicles were 3 radial arteries and nerves, 3 proper digital arteries and nerves, 1 radial artery, 1 superficial branch of radial nerve, 1 common digital artery and nerve. The histopathologic diagnosis of mass were 3 ganglions, 2 giant cell tumors, 2 epidermal cysts, 1 fibroma, and 1 benign spindle tumor. There were 2 cases of recurrence and secondary excisions were performed. Conclusion: Neurovascular pedicle injury can lead to serious complication like sensory and motor disorders, distal part ischemia, and so on. In case of mass suspected neurovascular invasion, accurate preoperative evaluation such as ultrasonography or MRI is necessary. To prevent any neurovascular related complication during mass excision, delicate surgical technique using a microscope becomes essential.

• Journal of Convergence Korean Medicine
• /
• v.6 no.1
• /
• pp.5-20
• /
• 2024

Objectives: This study was aimed to evaluate the hemodynamic feasibility using pulse parameters as a way to establish safe dose guidelines for Chunwangbosim-dan, and to provide a foundation for developing evidence-based guidelines for clinical use. Methods: Forty-one volunteers were recruited to participate in a study examining the changes in pulse wave characteristics following the ingestion of Chunwangbosim-dan, over a period of 2 weeks, and pulse wave measurements were taken before and after the administration. Pulse wave parameters were measured in this study using a 3-dimensional radial pulse tonometry device(DMP-Lifeplus). In addition, questionnaire, blood pressure, temperature, and body composition were also measured as secondary measures. Results: Fifteen minutes after administration of Chunwangbosim-dan, the non-adverse event group(non-AE) exhibited a statistically significant increase in several power and pressure-related parameters, including h1, h3, h4, h5, SA, PA and PW, while the adverse event group(AE) showed a trend of decreasing stroke volume and increasing Systemic Vascular Resistance Index(SVRI) and applied pressure. After 2 weeks of administration, non-adverse event group(non-AE) exhibited significant changes in standard deviation of pulse rate and HRV_LH ratio. Notably, there are significant differences between AE group and non-AE group in h4/h1, w/t, applied pressure, SV and pulse rate. Conclusion: These findings suggest that pulse parameters may be a useful way to establish safe dosing guidelines for Chunwangbosim-dan. Further research is needed to confirm these results and to develop evidence-based guidelines for clinical use.

• Journal of Cardiovascular Imaging
• /
• v.30 no.1
• /
• pp.50-58
• /
• 2022

BACKGROUND: Little is known regarding right ventricular (RV) remodeling immediately after Tetralogy of Fallot (TOF) repair. We sought to describe myocardial deformation by cardiac magnetic resonance imaging (CMR) after TOF repair and investigate associations between these parameters and early post-operative outcomes. METHODS: Fifteen infants underwent CMR without sedation as part of a prospective pilot study after undergoing complete TOF repair, prior to hospital discharge. RV deformation (strain) was measured using tissue tracking, in addition to RV ejection fraction (EF), volumes, and pulmonary regurgitant fraction. Pearson correlation coefficients were used to determine associations between both strain and CMR measures/clinical outcomes. RESULTS: Most patients were male (11/15, 73%), with median age at TOF repair 53 days (interquartile range, 13,131). Most patients had pulmonary stenosis (vs. atresia) (11/15, 73%) and 7 (47%) received a transannular patch as part of their repair. RV function was overall preserved with mean RV EF of 62% (standard deviation [SD], 9.8). Peak radial and longitudinal strain were overall diminished (mean ± SD, 33.80 ± 18.30% and -15.50 ± 6.40%, respectively). Longer hospital length of stay after TOF repair was associated with worse RV peak radial ventricular strain (correlation coefficient (r), -0.54; p = 0.04). Greater pulmonary regurgitant fraction was associated with shorter time to peak radial RV strain (r = -0.55, p = 0.03). CONCLUSIONS: In this small study, our findings suggest presence of early decrease in RV strain after TOF repair and its association with hospital stay when changes in EF and RV size are not yet apparent.

• Journal of the Ergonomics Society of Korea
• /
• v.36 no.5
• /
• pp.589-599
• /
• 2017

Objective: The objective of this study was to measure the upper-limb motions and postures of grapes-harvesting tasks using electrical goniometers and analyze the upper-limb motions in a kinematic way to assess the risk of musculoskeletal disorders. Background: Grapes farmers are exposed to various risk factors of musculoskeletal disorders (MSDs) such as repetitive upper-limb motions, non-neutral postures, and manual handling of heavy items. The farmers have to use scissors repetitively while harvesting grapes with their being arms elevated over the shoulder height, which presumed to increase the physical workload. It has been reported that the grapes farmers feel the harvesting task as the one of the hardest work in cultivating grapes. We tried measure the wrist and elbow angles while the farmers were carrying out harvesting tasks to understand how much workload the work impose on the farmers, which can be helpful in making interventions of preventing musculosksletal disorders among grapes farmers. Method: We measured joint angles at the right wrist and elbow with a wireless measuring system with two electrical goniometers from five grape farmers. The grapes-harvesting task was classified into 6 different subtasks: 1) searching, 2) picking, 3) cleaning, 4) carrying, 6) storing, and 7) miscellaneous tasks. The subtasks were compared by mean angles, 10%, 50%, and 90% APDF values of wrist flexion/extension, ulnar/radial deviation, and elbow flexion. Results: The Kruskal-Wallis tests showed that the 10th percentiles of APDF of ulnar/radial deviation and flexion/extension of the wrist significantly differs among subtasks (p<0.05). It was found that the farmers assumed more deviated wrist postures in the ulnar direction when they picking and adjusting the grapes. The use of scissors seemed to force the farmers to severely bend their wrist in the directions of ulnar deviation and flexion. The grapes-harvesting task showed similar wrist postures and motion with poultry deboning and milking tasks. Conclusion: The grapes harvesting tasks make the farmers take ulnar deviated and extended postures in the wrist. The use of scissors makes them take more severely deviated postures in the wrist. Safety guidelines including use of ergonomic scissors can be provided to the farmers to improve their work conditions. Application: The results of this study can be used as a basic data for the development of safety guidelines for agricultural work.

• Journal of the Korean Society of Safety
• /
• v.19 no.4 s.68
• /
• pp.123-128
• /
• 2004

This study investigated effect of arm posture, repetition of wrist motion and external load on perceived discomfort. The arm postures were controlled by shoulder flexion, elbow flexion, and ist motions such as flexion, extension, radial deviation and ulnar deviation. An experiment was conducted to measure discomfort scores for experimental treatments using the magnitude estimation, in which the L16 orthogonal array was adopted for reducing the size of experiment. The results showed that while the effect of the shoulder flexion, repetition of wrist motion and external load was statistically significant at $\alpha=0.05$or 0.10, that of the elbow and wrist motions was not. Discomfor ratings increased linearly as levels of wrist repetition and external load increased. This implies that the existing posture classification schemes such as OWAS, RULA, which do not properly consider effect of motion repetition and external load, may underestimate postural load. Based on the regression equation for wrist repetition and external load, isocomfort region indicating the region within which discomfort scores were expected to be the same was proposed. It is recommended that when assessing risk of postures or developing new posture classification schemes, motion repetition and external load as well as posture itself be fully taken into consideration for precisely evaluating postural stress.

• Journal of Applied Reliability
• /
• v.16 no.2
• /
• pp.147-154
• /
• 2016

Purpose: To evaluate statistical differences among three measurements of range of motion (ROM) with Rapael Smart Glove (RSG) group 1, 2 and manual goniometer group. To investigate reference value of the kinematic analysis for range of motion (ROM) of distal upper extremity with Rapael Smart Glove (RSG). Methods: Sixteen normal persons without limitation of motion (LOM) enrolled in the study. The study was performed at two separate times and by two investigators on 16 normal adults. We compared ROM with RSG for measuring joint angles. We compared degrees of forearm supination/pronation, wrist flexion/extension and radial deviation/ulnar deviation during ROM of 16 participants using RSG. After one week, degrees of each motion were measured in the same way by other investigator to evaluate the reliability. Results: Statistical differences among three groups were showed. Most results of paired t-test between two RSG groups were over 0.05 and exceptions are supination, extension, and finger %. Conclusion: Our findings demonstrate that ROM of normal persons obtained by kinematic analysis with RSG are not valid as normal reference value for distal upper extremity motion. But, the reliability of between two RSG groups was showed with paired t-test and Pearson's correlation except supination, extension and finger %.

• Korean Journal of Applied Biomechanics
• /
• v.24 no.3
• /
• pp.309-315
• /
• 2014

The aim of the present study was to investigate the effects of 6-week wrist resistance training on wrist torque control. Nineteen subjects were randomly assigned to either the wrist training group (n=9) or the control group (n=10). The training group performed wrist exercises for six directions (flexion, extension, pronation, supination, radial deviation, and ulnar deviation) while the control group did not. Testing for the isometric torque control error, one-repetition maximum (1-RM) strength, and isokinetic maximum torque (angular velocity of $60^{\circ}/s$ wrist movements) were conducted before and after six weeks of resistance training and after every two-week interval of training. The wrist training group showed significant decreases in isometric torque control error in all six directions after the 2-week resistance training, while the control group did not show significant increase or decrease. The training group showed significant increases in the maximum strength in all six directions assessed by 1-RM strength and isokinetic strength tests after the 4-week resistance training, while the control group did not show any statistically significant changes. This study shows that motor control ability significantly improves within the first two weeks of resistance training, while the wrist strength significantly improves within the first four weeks of resistance training in wrist training group compared to the control.