Changes of Gait Variability by the Attention Demanding Task in Elderly Adults

여상석 대한물리치료학회 2017 대한물리치료학회지 Vol.29 No.6

Purpose: Gait variability is defined as the intrinsic fluctuations which occur during continuous gait cycles. Increased gait variability is closely associated with increased fall risk in older adults. This study investigated the influence of attention-demanding tasks on gait variability in elderly healthy adults. Methods: We recruited 15 healthy elderly adults in this study. All participants performed two cognitive tasks: a subtraction dual-task (SDT) and working memory dual-task (WMDT) during gait plus one normal gait. Using the LEGSys+ system, we measured the coefficient of variation (CV %=100×[standard deviation/mean]) for participants’ stride time, stride length, and stride velocity. Results: SDT gait showed significant increment of stride time variability compared with usual gait (p<0.05), however, stride length and velocity variability did not difference between SDT gait and usual gait (p>0.05). WMDT gait showed significant increment of stride time and velocity variability compared with usual gait (p<0.05). In addition, stride time variability during WMDT gait also significantly increased compared with SDT gait (p<0.05). Conclusion: We reported that SDT and WMDT gait can induce the increment of the gait variability in elderly adults. We assume that attention demanding task based on working memory has the most influence on the interference between cognitive and gait function. Understanding the changes during dual task gait in older ages would be helpful for physical intervention strategies and improved risk assessment.

A Comparison of Dizziness Handicap Inventory Scores with Stability Index and Fourier Harmony Index in Healthy Individuals

여상석,류헌제 대한물리치료학회 2023 대한물리치료학회지 Vol.35 No.4

Purpose: The purpose of this study was to determine whether the degree of dizziness affects static balance due to the disruption or ab- sence of the senses involved in balance. To this end, the correlation between the Dizziness Handicap Inventory (DHI), which objectively evaluates dizziness, the Fourier Index (FI; Frequency bands of postural oscillation, F1, F2-4, F5-6, F7-8) and the Stability Index (ST), which evaluates static balance ability, were examined. Methods: This study investigated balance and dizziness issues in 30 healthy young adults. Participants underwent multiple tests like the DHI and tetra-ataxiometric posturography (Tetrax) under different conditions (eyes open/closed, standing on a foam-rubber pillow, and with the head in various orientations). Results: We found that F1 exhibited a weak positive correlation with dizziness under normal conditions, as well as when the eyes were closed (r = 0.396, p < 0.05) and the head was tilted back (r = 0.375, p < 0.05). Meanwhile, F5-6 showed a moderate positive correlation with dizziness in both head-back (HB: r = 0.471, p < 0.05) and head-forward postures (r = 0.404, p < 0.05). Lastly, both F7-8 and ST dem- onstrated a moderate positive correlation with dizziness when the head was in a forward posture (F7-8: r = 0.483; ST: r = 0.403, p < 0.05). Conclusion: The study results indicate that the severity of dizziness affects sensory systems and balance. It also suggests that head movements, especially forward and backward, further stimulate the vestibular system, intensifying dizziness, and balance problems in af- fected individuals.

관자 아래턱 장애에 따른 목뼈 가동 범위 제한과 보행 시 골반 가동성의 변화 연구

여상석 대한고유수용성신경근촉진법학회 2022 PNF and Movement Vol.20 No.3

Purpose: Temporomandibular disorder (TMD) is a common musculoskeletal problem that causes pain in and disability of masticatory muscles, the temporo-mandibular joint (TMJ), and related structures. The purpose of this study was to compare pressure pain thresholds (PPTs) of masticatory muscles, cervical ranges of motion (ROM), and pelvic mobility during gait of subjects with or without TMD. Methods: In this study, pain thresholds and changes in the mobility of the cervical vertebrae and pelvis were measured in 25 patients with TMD and 25 healthy controls. Using a pressure algometer, the pressure pain thresholds (PPTs) of the masseter and temporalis muscles were measured in both groups. A gyroscope sensor with a mobile application was used to determine cervical ROM in the frontal and sagittal planes. A 3D-motion analysis system was used to evaluate pelvic mobility in the sagittal, frontal, and transverse planes during gait. Results: The TMD group showed significantly decreased PPTs of masseter and temporalis muscles compared with the control group (p < 0.05). Cervical ROM in flexion, extension, and lateral bending were significantly decreased in the TMD group compared with the control group (p < 0.05). In addition, antero-posterior pelvic tilt was significantly decreased in the TMD group (p < 0.05). Conclusion: The results of the current study suggest that there are close anatomical and functional relationships between TMD and muscle chains related to the cervical spine and pelvis. Therefore, more comprehensive body posture assessments, especially of painful areas, should be undertaken when studying TMD patients.

Gait Recovery Characteristic According to the Injury Aspect of Descending Motor Pathway in a Chronic Stroke Patient: a Case Study

여상석 대한물리치료학회 2022 대한물리치료학회지 Vol.34 No.6

Purpose: The stroke patients have gait dysfunction due to impaired neural tracts; corticospinal tract (CST), corticoreticular pathway (CRP), and vestibulospinal tract (VST). In this study, we investigated characteristics of gait pattern according to the injury aspect of the neural track in a stroke patient. Methods: One patient and six control subjects of similar age participated. A 19-year-old male patient with spontaneous intracerebral hemorrhage on right basal ganglia, thalamus, corona radiata and cerebral cortex due to arteriovenous malformation rupture. Diffusion tensor imaging (DTI) data was acquired 21 months after the stroke. Kinematic and spatio-temporal parameters of gait were collected using a three-dimensional gait analysis system. Results: On 21 months DTI, the CST and CRP in affected hemisphere showed severe injury, in contrast, the VST in affected hemisphere showed intact integrity. Result of gait analysis, walking distance and speed were significantly decreased in a patient. The stance rate of unaffected lower limb, the swing rate of affected lower limb and the duration of double stance significantly increased compared with normal control. The knee and hip joint angle were significantly decreased in a patient. Conclusion: We found recovered independent gait ability may be associated with unimpaired VST in a patient with severe injury in CST and CRP.

만성 뇌졸중 환자에서 피질 척수로와 운동 능력의 상관관계 연구

여상석 대한고유수용성신경근촉진법학회 2014 PNF and Movement Vol.12 No.3

Purpose: The corticospinal tract (CST) is known to be an important pyramidal tract for walking and motor function. However, very little is known about the functional role of the CST in the recovery of motor function. In the current study, we investigated the relation between the CST and motor function in chronic hemiparetic stroke patients. Methods: Fifty-four patients and 20 normal subjects were recruited. The Functional Ambulation Category (FAC) was used in measurement of the walking ability. We classified patients into three groups according to the ability to walk independently: group A, patients who could not walk independently (FAC: 0-2); group B, patients who could walk independently (FAC: 3); and group C, patd walk functionally (stairs and uneven surfaces, FAC 4-5). The Motricity Index (MI) was used to measure the motor function of the affected upper and lower extremities (maximum score: 100). The fractional anisotropy (FA) value, apparent diffusion coefficient (ADC) value, and fiber volume of the CST were used for the diffusion tensor imaging (DTI) parameters. Results: In terms of the CST of the unaffected hemisphere, the FA value of group A was significantly lower than that of normal controls (p <0.05). The fiber volume of group C was significantly higher than that of normal controls (p <0.05). In contrast, the ADC values of all patient groups and the control group did not show any difference (p >0.05). In terms of lower MI and total MI, significant differences were observed between all patient groups (p <0.05). In addition, significant differences in terms of the upper MI scores were observed between groups A and C and between groups B and C (p <0.05); however, no significant difference was observed between groups A and B (p>0.05). Conclusion: The increased fiber volume of the CST in the unaffected hemisphere appears to be related to functional walking ability in chronic stroke patients. This result would be useful for elucidation of the neural recovery mechanism of walking and the investigation of new modalities for the recovery of walking following a stroke with CST injury. .

Precommissural Fornix in the Human Brain: A Diffusion Tensor Tractography Study

여상석,서정표,권용현,장성호 연세대학교의과대학 2013 Yonsei medical journal Vol.54 No.2

Purpose: Other than a single case report, no diffusion tensor tractography (DTT) studies of the precommissural fornix in the human brain have been conducted. In the current study, we attempted to visualize the precommissural fornix in the human brain using DTT. Materials and Methods: We recruited 36 healthy volunteers for this study. Diffusion tensor images were scanned using a 1.5-T scanner, and the precommissural fornix was analyzed using Functional Magnetic Resonance Imaging of the Brain (FMRIB) software. Values of fractional anisotropy (FA), mean diffusivity (MD), and tract volume of the precommissural fornix were measured. Results:The precommissural fornix originated from the hippocampal formation on each hemisphere as a crus; both crura were then joined to the body of the fornix. The body of the fornix continued anteriorly to the level just superior to the anterior commissure, where it divided into each column of the precommissural fornix. Each column descended anteriorly to the anterior commissure and terminated in the septal nuclei. Values of FA, MD, and tract volumes of the precommissural fornix did not differ between the right and left hemispheres (p>0.05). Conclusion: We believe that the methodology and results of this study would be helpful to future research on the precommissural fornix and in the elucidation of the pathology of diseases involving the precommissural fornix.

소뇌 손상에 의한 사지 마비 환자의 보행 및 운동 기능 회복 양상 연구

여상석,Sang-Seok Yeo 대한고유수용성신경근촉진법학회 2023 PNF and Movement Vol.21 No.3

Purpose: Cerebellar injury can be caused by a variety of factors, including trauma, stroke, and tumor. Cerebellar injury can manifest in different clinical symptoms and signs depending on the size and location of the injury. The purpose of this study was to examine and compare the recovery patterns of each motor function by tracking the motor levels of patients with cerebellar injury. Methods: This study recruited 11 patients with quadriplegia resulting from cerebellar injury. The motricity index (MI), modified Brunnstrom classification (MBC), and functional ambulation category (FAC) methods were used to evaluate motor levels. The motor function evaluation was performed immediately after the onset of the condition and at intervals of one month, two months, and six months after onset. Results: The MI values of the upper and lower extremities and hand function (MBC) indicated severe paralysis in the early stages of onset. Compared to the onset time, significant motor function recovery was observed after 1, 2, and 6 months (p < 0.05). In contrast, there was no significant pattern of recovery between 1, 2, and 6 months after onset (p > 0.05). FAC indicated showed significant recovery at one month compared to onset (p<0.05), and there was also a significant difference between 1 and 2 months (p < 0.05). On the other hand, there was no significant difference in FAC between 2 and 6 months (p > 0.05). Conclusion: Patients with cerebellar injury showed significant recovery in functions related to muscle strength and voluntary muscle control one month after onset and gradually recovered further over the next six months. On the other hand, gait function, which is closely related to balance, showed a relatively slow recovery pattern from the beginning of the disease to the six month follow-up.

Gait Characteristic in a Stroke Patient with an Intact Corticospinal Tract and Corticoreticular Pathway: A Case Study

여상석,조인희 대한물리치료학회 2018 대한물리치료학회지 Vol.30 No.2

Purpose: The prefrontal lobe, supplementary motor area, cerebellum, and basal ganglia are activated during gait. In addition, gait is controlled by nerves, such as the corticospinal tract (CST) and corticoreticular pathway (CRP). In this study, the presence of an injury to the CST and CRP was identified by diffusion tensor imaging and the characteristics of the gait pattern were investigated according to inferior cerebral artery infarction. Methods: One patient and six control subjects of a similar age participated. A 69-year-old female patient had an injury to the left basal ganglia, insular gyrus, corona radiata, dorsolateral prefrontal cortex, and postcentral gyrus due to an inferior cerebral artery infarction. Diffusion tensor imaging (DTI) data was acquired 4 weeks after the stroke. The kinematic and spatio-temporal parameters of gait were collected using a three-dimensional gait analysis system. Results: On 4 weeks DTI, the CST and CRP in the affected hemisphere did not show injury to the affected and unaffected hemisphere. Gait analysis showed that the cadence of spatio-temporal parameter was decreased significantly in the patient. The angle of the knee joint was decreased significantly in the affected and unaffected sides compared to the control group. Conclusion: The results of diffusion tensor imaging showed that although the patient was evaluated to be capable of an independent gait, the quality and quantity of gait might be reduced. This study could help better understand the gait ability analysis of stroke patients and the abnormal gait pattern of patients with a brain injury

Confabulation Following Injury of the Papez Circuit as a Result of Middle Cerebral Artery Infarction: A Diffusion Tensor Tractography Study

여상석,Yeo, Sang-Seok Korea Proprioceptive Neuromuscular Facilitation As 2016 PNF and Movement Vol.14 No.1

Purpose: In general, confabulation is defined as confusion of reality with past events without apparent prompting, in association with disruption of the capacity for retrieval and encoding of memory. We report on a patient who showed spontaneous confabulation associated with injury of the Papez circuit following middle cerebral artery (MCA) infarction. Methods: A 67-year-old female patient suffered cerebral infarct resulting from spontaneous MCA territory. After onset of the MCA infarct, she showed severe memory impairment and provoked confabulation. The Papez circuit was reconstructed for evaluation of part of it using diffusion tensor tractography (DTT). Fractional anisotropy (FA), mean diffusivity (MD), and tract volume were measured. Results: The right thalamocingulate tract showed a significant decrement of FA value and tract volume, and an increment of MD value by more than two standard deviations of that of normal control subjects. The tract volume in the left fornix and mammillothalamic tract decreased by more than two standard deviations of that of normal control subjects. Conclusion: Injuries of the Papez circuit were demonstrated in a patient who showed severe memory impairment and provoked confabulation following MCA infarct. We believe that analysis of the Papez circuit tract using DTT is useful in elucidating the cause of provoked confabulation in patients with MCA infarct.

발목관절의 각도가 무릎관절 폄근의 근활성도에 미치는 영향

여상석 ( Sang Seok Yeo ),권중원 ( Jung Won Kwon ),김중선 ( Chung Sun Kim ) 대한물리의학회 2009 대한물리의학회지 Vol.4 No.1

Purpose The purpose of this study was to find the effect of ankle joint angle on knee extensor electromyographic activity following knee extension exercise. Methods Ten male university students participated in the study. The subjects performed isometric maximal voluntary knee extensor contractions (MVC) and knee extensor EMG activity measured in with three different ankle joint angle, The EMG activity of rectus femoris (RF), vastus medialis (VM), vastus lateralis (VL) were measured using surface electromyography. Results EMG activity of vastus lateralis following the change of ankle joint angle was shown statistically significant difference, Conclusion Ankle plantar flexion position insrease EMG activity of vastus lateralis during knee extension exercise.