Changes in Lower Limb Muscle Activity during Lunge according to the Different Angle of Ankle Joint

Purpose@#This study compared the muscle activity of the lower limb according to the three types of fixed angles of the ankle joint during a lunge exercise. @*Methods@#Twenty healthy subjects performed the lunge motion in a trial including the three types of fixed angle. The lunge motion with a neutral, 20° dorsiflexion, and 20° plantarflexion of the ankle joint were randomized and measured repeatedly. The muscle activity of the rectus femoris (RF), vastus medialis (VM), vastus lateralis (VL), biceps femoris (BF), and semitendinosus (ST) was measured by surface electromyography. @*Results@#In the change in ankle joint angle, the RF, VL, BF, and ST muscle activity showed significant differences (p<0.05). In the 20° dorsiflexion position, the muscle activity of VL, BF, and ST showed a significant decrease compared to that in the neutral position (p<0.017). The muscle activity of RF and VL in the neutral position was greater than that in the 20° plantarflexion position (p<0.017). Only the muscle activity of the BF in the 20° plantarflexion position was significantly greater than the 20° dorsiflexion position (p<0.017). @*Conclusion@#These results revealed a difference in the muscle activity of lower extremities in the proximal region according to the angle of the ankle joint during the lunge.

Changes in Lower Limb Muscle Activity during Lunge according to the Different Angle of Ankle Joint

Purpose@#This study compared the muscle activity of the lower limb according to the three types of fixed angles of the ankle joint during a lunge exercise. @*Methods@#Twenty healthy subjects performed the lunge motion in a trial including the three types of fixed angle. The lunge motion with a neutral, 20° dorsiflexion, and 20° plantarflexion of the ankle joint were randomized and measured repeatedly. The muscle activity of the rectus femoris (RF), vastus medialis (VM), vastus lateralis (VL), biceps femoris (BF), and semitendinosus (ST) was measured by surface electromyography. @*Results@#In the change in ankle joint angle, the RF, VL, BF, and ST muscle activity showed significant differences (p<0.05). In the 20° dorsiflexion position, the muscle activity of VL, BF, and ST showed a significant decrease compared to that in the neutral position (p<0.017). The muscle activity of RF and VL in the neutral position was greater than that in the 20° plantarflexion position (p<0.017). Only the muscle activity of the BF in the 20° plantarflexion position was significantly greater than the 20° dorsiflexion position (p<0.017). @*Conclusion@#These results revealed a difference in the muscle activity of lower extremities in the proximal region according to the angle of the ankle joint during the lunge.

Implantable Bio-sensor Research for Administration of Chronic Disease / 계명의대학술지

Prolonged monitoring is more likely to result in an accurate diagnosis of atrial fibrillation patients than intermittent or short-term monitoring. In this study, we present an implantable ECG sensor to monitor atrial fibrillation patients in real time. The developed implantable sensor is composed of a micro controller unit, analog to digital converter, signal transmitter, antenna, and two electrodes. The sensor detects ECG signals from the two electrodes and transmits these signals to the external receiver that is carried by the patient. The sensor continuously transmits signals, so its battery consumption rate is extremely high. To overcome this problem, we consider using a wireless power transmission module in the sensor module. This module helps the sensor charge power wirelessly without holding the battery in the body. The size of the integrated sensor is approximately 0.12 x 1.18 x 0.19 inch. This sensor size is appropriate enough for cardiologists to insert the sensor into patients without the need for a major surgery. The data sampling rate was 300 samples/sec, and the frequency was 430 Hz for signal and power transmission.

Combination of Uric Acid and NT-ProBNP: A More Useful Prognostic Marker for Short-Term Clinical Outcomes in Patients with Acute Heart Failure

BACKGROUND/AIMS: In patients with heart failure (HF), N-terminal prohormone brain natriuretic peptide (NT-ProBNP) is a standard prognostic indicator. In addition, uric acid (UA) was recently established as a prognostic marker for poor outcome in chronic HF. The aim of this study was to determine the combined role of UA and NT-ProBNP as prognostic markers for short-term outcomes of acute heart failure (AHF). METHODS: The levels of UA and NT-ProBNP were determined in 193 patients (age, 69 +/- 13 years; 76 males) admitted with AHF. Patients were followed for 3 months and evaluated for cardiovascular events, defined as cardiac death and/or readmission for HF. RESULTS: Of the 193 patients, 23 (11.9%) died and 20 (10.4%) were readmitted for HF during the 3-month follow-up period. Based on univariate analysis, possible predictors of short-term cardiovascular events were high levels of UA and NT-ProBNP, low creatinine clearance, no angiotensin converting enzyme inhibitors or angiotensin receptor blockers, and old age. Multivariate Cox hazard analysis showed that UA levels were independently associated with increased incidence of cardiovascular events (hazard ratio, 1.115; 95% confidence interval, 1.006 to 1.235; p = 0.037). Kaplan-Meier survival analysis revealed that patients with UA levels > 8.0 mg/dL and NT-ProBNP levels > 4,210 pg/mL were at highest risk for cardiac events (p = 0.01). CONCLUSIONS: The combination of UA and NT-ProBNP levels appears to be more useful than either marker alone as an independent predictor for short-term outcomes in patients with AHF.

Support Vector Regression-based Model to Analyze Prognosis of Infants with Congenital Muscular Torticollis / 대한의료정보학회지

OBJECTIVES: Congenital muscular torticollis, a common disorder that refers to the shortening of the sternocleidomastoid in infants, is sensitive to correction through physical therapy when treated early. If physical therapy is unsuccessful, surgery is required. In this study, we developed a support vector regression model for congenital muscular torticollis to investigate the prognosis of the physical therapy treatent in infants. METHODS: Fifty-nine infants with congenital muscular torticollis received physical therapy until the degree of neck tilt was less than 5degrees. After treatment, the mass diameter was reevaluated. Based on the data, a support vector regression model was applied to predict the prognoses. RESULTS: 10-, 20-, and 50-fold cross-tabulation analyses for the proposed model were conducted based on support vector regression and conventional multi-regression method based on least squares. The proposed methodbased on support vector regression was robust and enabled the effective analysis of even a small amount of data containing outliers. CONCLUSIONS: The developed support vector regression model is an effective prognostic tool for infants with congenital muscular torticollis who receive physical therapy.

Implementation of Chest X-ray Observation Report Entry System / 대한의료정보학회지

OBJECTIVES: X-rays are widely used in medical examinations. In particular, chest X-rays are the most frequent imaging test. However, observations are usually recorded in a free-text format. Therefore, it is difficult to standardize the information provided to construct a database for the sharing of clinical data. Here, we describe a simple X-ray observation entry system that can interlock with an electronic medical record system. METHODS: We investigated common diagnosis indices. Based on the indices, we have designed an entry system which consists of 5 parts: 1) patient lists, 2) image selection, 3) diagnosis result entry, 4) image view, and 5) main menu. The X-ray observation results can be extracted in an Excel format. RESULTS: The usefulness of the proposed system was assessed in a study using over 500 patients' chest X-ray images. The data was readily extracted in a format that allowed convenient assessment. CONCLUSIONS: We proposed the chest X-ray observation entry system. The proposed X-ray observation system, which can be linked with an electronic medical record system, allows easy extraction of standardized clinical information to construct a database. However, the proposed entry system is limited to chest X-rays and it is impossible to interpret the semantic information. Therefore, further research into domains using other interpretation methods is required.

A New Method for Non-Invasive Measurement of Skin in the Low Frequency Range / 대한의료정보학회지

OBJECTIVES: The purpose of our study was to estimate skin structure and conductivity distribution in a cross section of local tissue using non-invasive measurement of impedance data. The present study was designed to evaluate the efficiency of skin depth information through computer simulations. The multilayer tissue model was composed of epidermis, dermis tissues, and subcutaneous. METHODS: In this study, electrical characteristics of skin models were used for conductivity of 0.13 S/m, 0.26 S/m, 0.52 S/m, permittivity of 94,000 F/m, and a frequency of 200 Hz. The effect of the new method was assessed by computer simulations using three-electrode methods. A non-invasive electrical impedance method has been developed for analysis using computer simulation and a skin electrical model with low frequency range. Using the three-electrode method differences through the potentials between measurement electrodes and reference electrodes can be easily detected. The Cole electrical impedance model, which is better suited for skin was used in this study. RESULTS: In this study, experiments using three-electrode methods were described by computer simulation based on a simple model. This electrical impedance model was fitted and developed in comparison with our model for measurement of skin impedance. CONCLUSIONS: The proposed electrical model for skin is suitable for use in interpretation of changes in impedance characterization of the skin. Using the computer simulation method, information on skin impedance depth can be more accurately developed and predicted.

Diagnostic Analysis of Patients with Essential Hypertension Using Association Rule Mining / 대한의료정보학회지

OBJECTIVES: The purpose of this study was to analyze the records of patients diagnosed with essential hypertension using association rule mining (ARM). METHODS: Patients with essential hypertension (ICD code, I10) were extracted from a hospital's data warehouse and a data mart constructed for analysis. Apriori modeling of the ARM method and web node in the Clementine 12.0 program were used to analyze patient data. RESULTS: Patients diagnosed with essential hypertension totaled 5,022 and the diagnostic data extracted from those patients numbered 53,994. As a result of the web node, essential hypertension, non-insulin dependent diabetes mellitus (NIDDM), and cerebral infarction were shown to be associated. Based on the results of ARM, NIDDM (support, 35.15%; confidence, 100%) and cerebral infarction (support, 21.21%; confidence, 100%) were determined to be important diseases associated with essential hypertension. CONCLUSIONS: Essential hypertension was strongly associated with NIDDM and cerebral infarction. This study demonstrated the practicality of ARM in co-morbidity studies using a large clinic database.

Variable Threshold based Feature Selection using Spatial Distribution of Data / 대한의료정보학회지

OBJECTIVE: In processing high dimensional clinical data, choosing the optimal subset of features is important, not only for reduce the computational complexity but also to improve the value of the model constructed from the given data. This study proposes an efficient feature selection method with a variable threshold. METHODS: In the proposed method, the spatial distribution of labeled data, which has non-redundant attribute values in the overlapping regions, was used to evaluate the degree of intra-class separation, and the weighted average of the redundant attribute values were used to select the cut-off value of each feature. RESULTS: The effectiveness of the proposed method was demonstrated by comparing the experimental results for the dyspnea patients' dataset with 11 features selected from 55 features by clinical experts with those obtained using seven other classification methods. CONCLUSION: The proposed method can work well for clinical data mining and pattern classification applications.

The Paper-Based Medical Record Compared to the Electronic Medical Record: Documentation and Agreement of Information / 대한의료정보학회지

OBJECTIVE: This aim of this study was to evaluate the quality and agreement of electronic medical records with paper-based medical records. METHODS: Data was collected from the paper-based medical records generated during 2004 and electronic medical records during 2007, in patients hospitalized for arterial fibrillation. The categories evaluated included the chief complaint, history of present illness, past illness, medication history, admission history, family history, allergies, smoking history, and drinking history in admission record. RESULTS: The electronic medical records scored higher for: the existence of a medical record, level of information in the medical record and agreement of information. However, there were some categories of disagreement between the information from doctors and nurses, and there were several categories with no record by doctors or nurses. CONCLUSION: The results of this study confirmed that the quality of the electronic medical record is better than that of paper-based medical with regard to: the existence of the record, level and agreement of information. However, there are discrepancies in the information contained within both types of records.

Development of Critical Pathway for Laparoscopic Assisted Vaginal Hysterectomy by CPA program / 대한의료정보학회지

OBJECTIVE: The aim of this study was to develop critical pathway for post operation care of laparoscopic assisted vaginal hysterectomy with time and cost effectiveness using a clinical pathway assistant program (MDCPA(TM), MDware Co.) METHODS: Procedure was done with the following steps; establishment of conceptual framework, development of preliminary critical pathway using CPA program, expert validity test, and confirmation of final critical pathway. RESULTS: Preliminary critical pathway was extracted by CPA program, and this result was verified by expert validity test. The process of data collection and analysis to develop the preliminary critical pathway was accomplished automatically by CPA program. The patients' hospitalization period in the aspect of time and cost effectiveness was confirmed as 6 days, and each item of assessment, test, medication, treatment, diet, activity, and teaching were finalized. CONCLUSION: The CPA program can automate the complicated process, which contains collecting and cleaning the large size EMR data, classifying and confirming the items in critical pathway, so that the time and cost to develop a critical pathway can be reduced. This program is expected to be used for development of critical pathway in a variety of clinical settings in the aspect of time and cost effectiveness.

Development of Korean Model for Independent Organ Procurement Organization / 대한이식학회지

PURPOSE: The aims of this project were to increase organ donation by developing potential brain dead donor actively and to provide basic data to settle up independent Organ Procurement Organization (OPO) in Korea. METHODS: Hospital based Organ Procurement Organization (HOPO) of Keimyung university worked as a regional OPO and all the reported potential brain dead patient were treated by OPO team during May through October, 2007. Every reported and confirmed brain dead patient was evaluated for their eligibility of organ donation and these organs were allocated by Korean Network for Organ Sharing (KONOS). In order to increase the development of organ donation, campaign was done for public and medical personnels. To estimate the capacity of brain death donor pool, medical records of the dead patients with brain injury were evaluated. Accommodations and educations to the care-giver to the potential donor, neurosurgeon, neurologist and emergency department physicians were also done. For standardization of potential donor care, frame a clinical pathway of the care of the potential donor from the data of computerized records. The cash flow of whole process from developing potential donor to final procurement of organs were calculated to provide minimum expenses for operating Independent OPO in our environment. RESULTS: Total 33 solid organs were procured from 11 brain dead donor during the experimental period. Twelve more organs were possible to donate but not procured because there were no matched recipient at that time. The reported number of potential donor was increased 2.5 times, compare to the same period of previous year (19 from 5 hospital in 2006 but 47 from 14 collaborating hospitals in 2007). Among 47 notified potential donor, only 11 were succeeded to procure. The reasons of failure for procurement in 36 patients were no familial consent in 12, poor patient condition to donate in 9, not in brain death criteria in 15. These results mean that we have at least 21 more potential donors if we can get familial consent and use marginal donor, and early notification. Mean medical expenses were 3 million won for individual expense beside insurance coverage and 5 million won for management expense of donor care from the detection to organ procurement. CONCLUSION: Our results showed the number of the potential donor and actual organ donation can be increased by continued active relationship with regional hospital and adequate care of the donor. The big gap between the profit from our donor care and calculated donor management expenses of IOPO can be progressively covered by increasing number of brain dead donor, increasing procurement rate and increasing organ fee paid by recipient. But for a certain periods, financial support is necessary to settle up IOPO. Our result can be used as a basic data for management plan of IOPO in the future.