• Proceedings of the Korean Society of Precision Engineering Conference
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• 2013.05a
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• pp.977-978
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• 2013

• Journal of Korean Neurosurgical Society
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• v.57 no.4
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• pp.303-306
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• 2015

Deep brain stimulation (DBS) of the pedunculopontine nucleus (PPN) is a novel therapy developed to treat Parkinson's disease. We report a patient who underwent bilateral DBS of the PPN and subthalamic nucleus (STN). He suffered from freezing of gait (FOG), bradykinesia, rigidity and mild tremors. The patient underwent bilateral DBS of the PPN and STN. We compared the benefits of PPN-DBS and STN-DBS using motor and gait subscores. The PPN-DBS provided modest improvements in the gait disorder and freezing episodes, while the STN-DBS failed to improve the dominant problems. This special case suggests that PPN-DBS may have a unique role in ameliorating the locomotor symptoms and has the potential to provide improvement in FOG.

• Korean Journal of Applied Biomechanics
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• v.26 no.3
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• pp.293-301
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• 2016

Objective: The purpose of this study was to analyze the effects of freezing of gait and visual information on the static postural control ability in patients with Parkinson's Disease (PD) during the bipedal stance with feet together. Method: This study included a total of 36 patients with PD; the freezer group included 17 PD patients (age: $69.3{\pm}6.2yrs$, height: $159.6{\pm}9.0cm$, weight: $63.4{\pm}9.78kg$) and the nonfreezer group included 19 PD patients (age: $71.4{\pm}5.6yrs$, height: $155.8{\pm}7.1cm$, weight: $57.7{\pm}8.6kg$). Static postural control ability was analyzed using variables of center of pressure (COP) and dividing by mediolateral, anteroposterior, and integration factors during a bipedal stance with the eyes open and closed. Results: Freezers and nonfreezers showed increases in anteroposterior velocity, mediolateral velocity, averaged velocity, and mediolateral 95% edge frequency when visual information was blocked. Additionally, freezers had greater anteroposterior range, 95% confidence ellipse area, and COP anteroposterior mean position than nonfreezers. Conclusion: Freezers and nonfreezers showed a reduction in static postural control ability when visual information was blocked. Additionally, the results of this study found a significant difference in static postural control ability between freezers and nonfreezers with PD. In particular, anteroposterior range, 95% confidence ellipse area, and COP anteroposterior mean position might be used to distinguish between freezers and nonfreezers with PD.

• Proceedings of the Korean Institute of Information and Commucation Sciences Conference
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• 2019.05a
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• pp.283-284
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• 2019

In the last decades patient's suffering with Parkinson's disease is increasing at a rapid rate and as per prediction it will grow more rapidly as old age population is increasing at a rapid rate through out the world. As the performance of wearable sensor based approach reached to a new height as well as powerful machine learning technique provides more accurate result these combination has been widely used for assessment of various neurological diseases. ON state is the state where the effect of medicine is present and OFF state the effect of medicine is reduced or not present at all. Classification of ON/OFF state for the Parkinson's disease is important because the patients could injure them self due to freezing of gait and gait related problems in the OFF state. in this paper wearable sensor based approach has been used to collect the data in ON and OFF state and machine learning techniques are used to automate the classification based on the gait pattern. Supervised machine learning techniques able to provide 97.6% accuracy while classifying the ON/OFF state.

• Korean Journal of Applied Biomechanics
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• v.28 no.1
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• pp.19-27
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• 2018

Objective: This study aimed to analyze the effects of freezing of gait on spatiotemporal variables, ground reaction forces (GRFs), and joint moments during the sit-to-walk task at the preferred and maximum speeds in patients with Parkinson's disease (PD). Method: The subjects were classified by a neurologist into 12 freezers, 12 non-freezers, and 12 controls. Sit-to-walk parameters were measured during three repetitions of the task in a random order at the preferred and maximum possible speeds. Results: In the sit-to-walk task at the preferred speed, the freezers and non-freezers exhibited a higher peak anterior-posterior GRF (p<0.001) in the sit-to-stand phase and lower step velocity (p<0.001), step length (p<0.001), and peak anterior-posterior GRF (p<0.001) in the first-step phase than the controls. The freezers had higher peak anterior-posterior GRF (p<0.001) and peak moment of the hip joint (p=0.008) in the sit-to-stand phase than the non-freezers. In the sit-to-walk phase at the maximum speed, the freezers and non-freezers had lower peak moment of the hip joint (p=0.008) in the sit-to-stand phase than the controls. The freezers and non-freezers displayed lower step velocity (p<0.001) and peak anterior-posterior GRF (p<0.001) in the first-step phase than the controls. The freezers showed higher peak moments of the hip joint in the sit-to-stand phase than the non-freezers (p=0.008). Conclusion: The PD patients had reduced control ability in sit-to-stand motions for efficient performance of the sit-to-walk task and reduced performance in the sit-to-walk task. Furthermore, the freezers displayed reduced control ability in the sit-to-stand task. Finally, the PD patients exhibited a lower ability to control dynamic stability with changes in speed than the controls.

• Journal of the Korean Society for Precision Engineering
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• v.25 no.3
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• pp.165-175
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• 2008

An ankle-foot orthosis(AFO) is a brace for persons with gait disabilities to support or replace the function of ankle joint. Ankle-foot orthoses(AFO's) are usually prescribed to alleviate the drop-foot by constraining the excessive plantar flexion. The shape and the strength of the AFO are often based on 'trial and error' due to a lack of knowledge of the stress distribution in the AFO. In this study, an improved stress-freezing method was proposed to measure the stress distribution characteristics in the AFO. As a result, a photoelastic material with low freezing temperature was developed to measure the stresses under a person's direct contact loading condition. The three-dimensional stress-1rozen photoelastic models of AFO's for five stages of stance phase such as heel contact, foot flat, mid stance, heel off, and toe off were produced. The results of photoelastic analysis revealed that the stresses developed in the AFO were varied considerably from tensile to compressive or vice versa, during walking. At the posterior part of ankle joint in the AFO, the maximum compressive stress of 1.81MPa was observed in the mid stance, and the maximum tensile stress of 0.74MPa was observed during heel contact. The overall stress levels in the AFO's were low in the toe off phase. The results suggested that the posterior part of ankle joint might be the most fragile part in the AFO.

• Journal of Biomedical Engineering Research
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• v.34 no.4
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• pp.182-188
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• 2013

This study aims to develop a practical algorithm which can detect freezing of gait(FOG) in patients with Parkinson's disease(PD). Eighteen PD patients($68.8{\pm}11.1yrs.$) participated in this study, and three($68.7{\pm}4.0yrs.$) of them showed FOG. We suggested two time-domain algorithms(with 1-axis or 3-axes acceleration signals) and compared them with the frequency-domain algorithm in the literature. We measured the acceleration of left foot with a 3-axis accelerometer inserted at the insole of a shoe. In the time-domain method, the root-mean-square(RMS) acceleration was calculated in a moving window of 4s and FOG was defined as the periods during which RMS accelerations located within FOG range. The parameters in each algorithm were optimized for each subject using the simulated annealing method. The sensitivity and specificity were same, i.e., $89{\pm}8%$ for the time-domain method with 1-axis acceleration and were $91{\pm}7%$ and $90{\pm}8%$ for the time-domain method with 3-axes acceleration, respectively. Both performances were better in the time-domain methods than in the frequency-domain method although the results were statistically insignificant. The amount of calculation in the time-domain method was much smaller than in the frequency-domain method. Therefore it is expected that the suggested time domain algorithm would be advantageous in the systematic implementation of FOG detection.

• Korean Journal of Applied Biomechanics
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• v.22 no.3
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• pp.333-339
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• 2012

Freezing of gait is a severely problem in people with Parkinson's disease. The purpose of this study was to investigate the muscle activities of adductor longus, gluteus medius, gluteus maximus, biceps femoris, rectus femoris, gastrocnemius, and tibialis anterior using Noraxon 8 channels EMG system during stop task in patients with Parkinson's disease. Seven parkinson's patients and age matched normal participants were recruited in the study. Filtered EMG signals were rectified, smoothed and integrated. To control for the altered timing and magnitude of activity, iEMG was normalized for time and peak value. The results indicated that the patients with Parkinson showed decreased gait cycle, stance phase, swing phase time, swing phase time ratio and increased stance phase time ratio than normal participants. The patients with Parkinson showed decreased gastrocnemius muscle activity time ratio, while increased tibialis anterior muscle activity time ratio than normal participants. During stance phase before stop, the patients with Parkinson showed relatively lower average and peak iEMG in anterior tibialis and gastrocnemius muscle than normal participants. During swing phase before stop, the patients with Parkinson showed relatively higher average iEMG in gastrocnemius muscle than normal participants. During stop phase, the patients with Parkinson showed relatively lower average and peak iEMG in anterior tibialis and gastrocnemius muscle than normal participants.

• Journal of Acupuncture Research
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• v.24 no.4
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• pp.43-54
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• 2007

Objectives : This study was designed to evaluate the effect of acupuncture with various scales on symptoms of Idiopathic Parkinson's disease. Methods: Subjects were voluntarily recruited through newspapers and internet advertisement. All the subjects were confirmed as idiopathic parkinson's disease by a neurologist. The acupuncture therapy was performed twice a week for 4 weeks by oriental medical doctor at Kyung-hee University hospital. Patients were randomly assigned to three groups : sham acupuncture group, acupuncture treatment group and Sasang-Constitution acupuncture treatment group. Acupun cture points used in acupuncture treatment group were $GB_{34}$, $LR_3$, and $ST_{36}$, which were proven to be effective in rat Parkinson's disease study. Acupuncture points used in sham treatment were non-acupoints near $GB_{34}$, $LR_3$, and $ST_{36}$. In Sasang-Constitution acupuncture treatment, we classfied Sasang constitution of patients by QSCCII. Acupuncture was applied based on theory of Korean medicine. The patient's symptoms were assessed at baseline and after 4 weeks of treatment by one evaluator with Unified Kingdom Parkinson's Disease Rating Scale (UPDRS), modified Hoehn-Yahr(H-Y) stage, and Schwab & England activ ity of daily living and freezing of gait questionnaire (FOGQ). Results : The results were as follows ; 1. UPDRS IV score differences between sham group and Sasang-Constitution acupuncture treatment were statistically significant(p=0.001). 2. UPDRS total score differences between Sasang-Constitution acupuncture treatment and acupuncture treatment group, Sasang-Constitution acupuncture treatment and sham group were statistically significant(p=0.041, p=0.014). 5. FOGQ score differences between Sasang-Constitution acupuncture treatment and acupuncture treatment group, Sasang-Constitution acupuncture treatment and sham group were statistically significant(p=0.001, p=0.001). Conclusion : The results suggest Sasang-Constitution acupuncture treatment can be applicable to improve symptoms in patients with idiopathic Parkinson's disease.

• Journal of Acupuncture Research
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• v.23 no.6
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• pp.153-164
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• 2006

Introduction : The Aim of the Study Is to Investigate the Characteristics of Yangdorak m the Patients with Idiopathic Parkinson's Disease. Methods : Subjects Were Voluntarily Recruited by Newspapers And Internet. All the Subjects Were Confirmed as Idiopathic Parkinson's Disease by a Neurologist. The Patient's Symptoms Were Assessed by Unified Parkinson's Disease Rating Scale (UPDRS), Hoehn-Yahr (H-Y) Stage, Schwab & England Activity of Daily Living And Freezing of Gait Questionnaire(FOGQ). Sasang Constitution Was Differentiated by QSCCII. Yangdorak Was Measured after 15 minutes' Bed Rest Results : The Results Were as Follows; 1. The Average Value of Yangdorak m 50 Patients with Parkinson's Disease Was $39.01{\pm}17.97$. 2. The Mean Values of Fl, F2, F3, F4, F5 and F6 were under 40. 3. The Number of Pyesaek Was Significantly Increased According to H-Y Stage. 4. The Yangdorak Value Had No Significant Correlation between UPDRS, H-Y Stage and Duration. 5. There Was No Significant Difference in the Value of Yangdorak among Sasang Constitutions. Conclusion : This Study Suggests that Yangdorak Can Be Used as a Assistant Tool to Investigate the Patients of Parkinson's Disease. Further Study on the Yangdorak And Parkinson's Disease Is Recommended.