Seung Hoon Han

New synthetic route for preparing rattle-type silica particles with metal cores

Rattle-type silica particles with metal cores, applicable to catalysts and metal/inorganic composite coating materials, were prepared by the pre-shell/post-core method that can control the size of metal cores inside silica capsules and exchange from metal cores into different ones with a metal displacement reaction.

Common Peroneal Nerve Compression by a Popliteal Venous Aneurysm

A 58-yr-old man with a right foot drop and a sensory change in the right calf and foot, which developed after a bladder operation, was referred to our clinic for an electrodiagnostic evaluation. Neurologic examination showed grade 1 weakness of the right ankle in dorsiflexion, great toe in dorsiflexion, and ankle in eversion. In addition, the patient complained of pain and a tingling sensation in the right calf and foot. Electrodiagnostic findings were consistent with right common peroneal nerve palsy at the level of the fibula head. In addition, duplex ultrasonography, computed tomography angiography, and magnetic resonance imaging revealed a right popliteal venous aneurysm and impingement of the right common peroneal nerve between the aneurysm and the belly of the biceps femoris muscle. After resection of the aneurysm, his sensory symptoms and motor strength of the right foot and calf gradually improved. This case suggests that compression by the venous system should be considered when there is clinical evidence of focal neuropathy but no abnormal findings at common entrapment sites.

The effect of an arm sling on energy consumption while walking in hemiplegic patients: a randomized comparison

Objective: To evaluate the effect of an arm sling on gait speed and energy efficiency of patients with hemiplegia. Design: A randomized crossover design. Setting: A rehabilitation department of a university hospital. Subjects: Thirty-seven outpatients with hemiplegia were included in this study. Interventions: All patients walked on a 20-m walkway twice on the same day, randomly with and without an arm sling, at a self selected speed. Main measures: The heart rate, gait speed, oxygen cost and oxygen rate were measured on all patients. We analysed all values with and without an arm sling and also compared them after all patients being stratified according to demographic and clinical characteristics. Results: When we compared the heart rate between walking with (90.7 ± 17.2 beats/min) and without (91.2 ± 18.6 beats/min) the arm sling, it was significantly decreased while walking with the arm sling. When we compared the gait speed between walking with (32.8 m/min) and without (30.1 m/min), it was significantly increased with the arm sling walking. The O2 rate in hemiplegic patients walking with the arm sling was significantly decreased by 7%, compared to walking without arm sling (5.8 mL/kg min and 6.2 mL/kg min, respectively). The O2 cost in hemiplegic patients walking without arm sling was significantly 1.4 times greater than walking with it (0.2 mL/kg m and 0.3 mL/kg m, respectively). Conclusion: An arm sling can be used to improve the gait efficiency.

A randomized comparison of energy consumption when using different canes, inpatients after stroke

Objectives: To investigate the differences in oxygen consumption associated with gait in hemiplegic patients according to the type of cane they use. Design: A randomized crossover design. Setting: University hospital-based rehabilitation center, Korea. Subjects: Thirty consecutive patients (mean ± SD age, 56.3 ± 3.2 years) with chronic stroke, 17 (56.7%) males and 13 (43.3%) females. Interventions: At approximately the same time of day for three consecutive days, each participant completed a walk with one of three randomly assigned types of canes: a single-point cane, a quad cane, and a hemi-walker. Main outcome measure: Energy expenditure (O2 rate, mL/kg/min), energy cost (O2 cost, mL/kg/m), and heart rate (HR) via a portable gas analyzer, a 10-meter walk test (10MWT), and a 6-minute walk test (6MWT). Results: Energy expenditure, gait endurance, and gait velocity for a single-point cane were higher (p<0.001 or p=0.005) than for any other type of cane. Energy cost (0.5 ± 0.2 mL/kg/m vs. 0.6 ± 0.2 mL/kg/m vs. 0.6 ± 0.2 ml/kg/m, respectively, p=0.001) was lower for the single-point cane, except for HR (p ≥ 0.05) after the Bonferroni correction (0.05/5=0.01). Conclusions: A single-point cane requires less oxygen use at a given speed, or permits greater speed for the same oxygen consumption.

The Prevalence and Characteristics of Depression in Work-related Musculoskeletal Disease

Objective To reveal the relationship between depression and WMSD. Method Five physiatrists participated in the workplace musculoskeletal survey and diagnosed 724 office workers with WMSD by performing detailed history taking and physical examination. All subjects were asked to answer the Korean version of the Beck depressive inventory (K-BDI), and to express their pain according to the visual analogue scale (VAS) score. We categorized the subjects into 4 groups, myofascial pain syndrome (MPS), herniated intervertebral disk (HIVD), tenosynovitis, and others, and investigated the prevalence of depression in desk workers and relationship between WMSD and depression, and we compared pain intensity between the depression and non-depression groups. Correlation analysis was carried out between K-BDI and VAS scores in each group. Results The mean K-BDI score were 8.7±6.68. The prevalence of depression was higher in females than in male, and there was no relationship between age and depression. There was a significant connection between HIVD and depression (p<0.05). However, the other groups did not have significant connection to depression. The VAS score (5.02) of the depression group was significantly higher than that (4.10) of the non-depression group. In addition, there was a significant difference of VAS scores between the depression group and non-depression group in each disease group. Conclusion The mean VAS score of the depression group in WMSD was significantly higher than in the non-depression group. The correlation between BDI and VAS scores in the subjects was present, and the highest was in the HIVD group.

Change in Musculoskeletal Pain in Patients With Work-Related Musculoskeletal Disorder After Tailored Rehabilitation Education: A One-Year Follow-Up Survey

Objective To apply tailored rehabilitation education to video display terminal (VDT) workers with musculoskeletal pain and to assess changes in musculoskeletal pain after rehabilitation education. Methods A total of 8,828 VDT workers were screened for musculoskeletal disorders using a self-report questionnaire. Six hundred twenty-six VDT workers selected based on their questionnaires were enrolled in musculoskeletal rehabilitation education, which consisted of education on VDT syndrome and confirmed diseases, exercise therapy including self-stretching and strengthening, and posture correction. One year later, a follow-up screening survey was performed on 316 VDT workers, and the results were compared with the previous data. Results Compared with the initial survey, pain intensity was significantly decreased in the neck area; pain duration and frequency were significantly decreased in the low back area; and pain duration, intensity, and frequency were significantly decreased in the shoulder and wrist after tailored rehabilitation education. In addition, pain duration, intensity, and frequency showed a greater significant decrease after tailored rehabilitation education in the mild pain group than in the severe pain group. Conclusions This study found that work-related musculoskeletal pain was reduced after tailored rehabilitation education, especially in the shoulder, wrist, and low back.

Causes of Hand Tingling in Visual Display Terminal Workers

Objective To offer the basic data about the causes and distribution of hand tingling, symptoms and physical findings, and pressure pain threshold in desk workers. Methods Five physiatrists participated in the screening test composed of history and physical examination. A total of 876 desk workers were evaluated and of them 37 subjects with hand tingling were selected. For further analyzing, detailed history taking and meticulous physical examination were taken. Pressure pain threshold (PPT) at the infraspinatus, upper trapezius, flexor carpi radialis, rhomboideus, and flexor pollicis longus were examined. PPT measurements were repeated three times with two minute intervals by a pressure algometer. Electrodiagnostic study was done to detect potential neurologic abnormalities. Results The causes of hand tingling in order of frequency were: myofascial pain syndrome, 68%; cervical radiculopathy, 27%; rotator cuff syndrome, 11%; tenosynovitis, 8%; and carpal tunnel syndrome, 5%. The location of trigger points in the myofascial pain syndrome, which were proven to evoke a tingling sensation to the hand in order of frequency were: infraspinatus, 65.4%; upper trapezius, 57.7%; flexor carpi radialis, 38.5%; rhomboideus 15.4%; and flexor pollicis longus 11.5%. The PPT of the affected side was significantly lower than that of the unaffected side in myofascial pain syndrome (p<0.05). Conclusion The most common cause of hand tingling in desk workers was myofascial pain syndrome rather than carpal tunnel syndrome. Common trigger points to evoke hand tingling were in the infraspinatus and upper trapezius.

A case of rheumatoid arthritis with unilateral knee synovial hypertrophy in hemiplegia.

A 64-year-old woman suffering right hemiplegia came in with pain and swelling on her left knee, general weakness and poor oral intake for 2 months. On physical examination we were able to palpate a mass with irregular margin around the left suprapatellar area. From the results of the magnetic resonance imaging (MRI), synovial proliferative disease, infectious arthritis, or gouty arthritis was suspected. We performed a blood laboratory test to detect rheumatologic diseases, knee joint aspiration, and bone scan for differential diagnosis, and were able to diagnose rheumatoid arthritis (RA) from the results of blood laboratory, physical examination, and bone scan. Consequently, we started medications for controlling RA. Herein, we report a case of rheumatoid arthritis with unilateral knee synovial hypertrophy in hemiplegia. If a right hemiplegic patient has recurrent pain on the left knee and synovial hypertrophy, and fails to respond to treatment for osteoarthritis, early detection by evaluation for rheumatic disease is crucial to prevent severe sequelae influencing rehabilitation of hemiplegia.

Ultrasound versus fluoroscopy-guided medial branch block for the treatment of lower lumbar facet joint pain: A retrospective comparative study

Abstract The aim of this study was to compare the mid-term effects and benefits of ultrasound (US)-guided and fluoroscopy (FL)-guided medial branch blocks (MBBs) for chronic lower lumbar facet joint pain through pain relief, functional improvement, and injection efficiency evaluation. Patients with chronic lumbar facet joint pain who received US (n = 68) or FL-guided MBBs (n = 78) were included in this retrospective study. All procedures were performed under FL or US guidance. Complication frequency, therapeutic effects, functional improvement, and the injection efficiency of MBBs were compared at 1, 3, and 6 months after the last injection. Both the Oswestry Disability Index (ODI) and the verbal numeric pain scale (VNS) improved at 1, 3, and 6 months after the last injections in both groups. Statistical differences were not observed in ODI and VNS between the groups (P > .05). The proportion of patients who reported successful treatment outcomes showed no significant differences between the groups at different time points. Logistic regression analysis showed that sex, pain duration, injection methods, number of injections, analgesic use, and age were not independent predictors of a successful outcome. US guidance was associated with a significantly shorter performance time. US-guided MBBs did not show significant differences in analgesic effect and functional improvement compared with the FL-guided approach. Therefore, by considering our data from this retrospective study, US-guided MBBs warrant consideration in the conservative management of lower lumbar facet joint pain.

Ion sheath expansion for a target voltage with a finite risetime

Properties of the ion sheath expansion in plasma are investigated for a target voltage with a finite rise time. A theoretical model for ion sheath expansion is developed when the negative target voltage increases linearly. The theory predicts that the sheath expansion is proportional to the square root of time at the beginning and is proportional to the 56 power of time later on. An experimental measurement has been carried out and the measured data are compared with theoretical results. It is shown that the sheath front propagates very fast at the beginning and slows down later, even for continuously rising negative voltage on target.