• Journal of the Korean Society of Radiology
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• v.82 no.6
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• pp.1556-1564
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• 2021

Purpose This study aimed to apply MR elastography (MRE) to achieve in vivo evaluation of the elastic properties of thigh muscles and validate the feasibility of quantifying the elasticity of normal thigh muscles using MRE. Materials and Methods This prospective study included 10 volunteer subjects [mean age, 32.5 years, (range, 23-45 years)] who reported normal activities of daily living and underwent both T2-weighted axial images and MRE of thigh muscles on the same day. A sequence with a motion-encoding gradient was used in the MRE to map the propagating shear waves in the muscle. Elastic properties were quantified as the shear modulus of the following four thigh muscles at rest; the vastus medialis, vastus lateralis, adductor magnus, and biceps femoris. Results The mean shear modulus was 0.98 ± 0.32 kPa and 1.00 ± 0.33 kPa for the vastus medialis, 1.10 ± 0.46 kPa and 1.07 ± 0.43 kPa for the vastus lateralis, 0.91 ± 0.41 kPa and 0.93 ± 0.47 kPa for the adductor magnus, and 0.99 ± 0.37 kPa and 0.94 ± 0.32 kPa for the biceps femoris, with reader 1 and 2, respectively. No significant difference was observed in the shear modulus based on sex (p < 0.05). Aging consistently showed a statistically significant negative correlation (p < 0.05) with the shear modulus of the thigh muscles, except for the vastus medialis (p = 0.194 for reader 1 and p = 0.355 for reader 2). Conclusion MRE is a quantitative technique used to measure the elastic properties of individual muscles with excellent inter-observer agreement. Age was consistently significantly negatively correlated with the shear stiffness of muscles, except for the vastus medialis.

• Journal of dental hygiene science
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• v.3 no.2
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• pp.59-66
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• 2003

As a basic research material to make more efficient healthcare and health promotion for dental hygienists, this study intends to determine which factors may affect their awareness of occupational diseases. For this sake, this study attempted to investigate into a variety of literatures and data, and applied a questionnaire survey to 160 dental hygienists for about 5 months(from June to October 2003), who were all employed in domestic dental clinics or offices. As a result of analysis, this study can be concluded as follows: (1) The result of analyzing how dental hygienists recognized their occupational diseases showed that 'stiffness in muscle, neck or shoulder due to intensive use of specific physical regions' and 'stress resulting from the attributes of each task' reached the highest awareness(90.6%) of all, which was followed by 'lower eyesight due to detailed or even sophisticated tasks for many hours(65%)' and 'symptoms of ruptured disk due to standing tasks as dental hygienists do for many hours(62.5%).' (2) The result of analyzing how dental hygienists recognize their occupational diseases showed that their awareness averaged 7.28 points out of 14 points, which implies that their awareness of occupational diseases is not very high. Meanwhile, the result of examining how they recognize detrimental or harmful properties of given materials against human body showed that a majority of total respondents(74.4%) regarded given materials as detrimental to human body. (3) The result of examining how dental hygienists recognize their occupational diseases showed that a majority of total respondents(91.9%) identified their own occupational diseases. Many of total respondents(41.9%) pointed out that environmental improvement around workshop in each clinic or office should be foremost prerequisite to health and welfare for dental hygienists. Next, 34.4% of total respondents pointed out the necessity to perform in-house health diagnosis and examination on a regular basis, and 13.1% of total respondents thought it necessary to carry on healthcare education into harmful properties in the aspect of dental materiology, respectively.

• Clinics in Shoulder and Elbow
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• v.10 no.1
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• pp.92-98
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• 2007

Introduction: The treatment of proximal humeral fracture is traditionally determined by Neer's classification system. The severely displaced three-part or four-part fracture is an indication for primary hemiarthroplasty. The current authors report the clinical results of 10 patients who received hemiarthroplasty for proximal comminuted fractures. The minimum follow-up period was 12 months. Materials and Methods: The current authors studied 10 patients who, between July 1999 and March 2005, each received hemiarthroplasty for a proximal humeral fracture of one shoulder. According to Neer's classification system, 5 of the patients had three-part fractures, and 5 of the patients had 4-part fractures. The mean interval between trauma and hemiarthroplasty was 6.1 days. The mean age of the 6 female and 4 male patients was 67.4 years(range: 56 to 76). Shoulder function was evaluated using the Constant score, the Simple Shoulder Test, and the modified UCLA score. Results: The mean Constant score was 51.4(range: 34 to 60). The mean modified SST score was 7.8 out of 12 tasks. Excluding the one patient who had also sustained an axillary artery rupture and a brachial plexus injury after the initial trauma, the mean Constant score for the remaining 9 patients was 53.5(range: 44 to 60), and the mean SST score was 7.2 tasks. The modified UCLA score averages for pain, function, and active forward flexion and strength were, respectively, 8.2($6{\sim}10$), 6.6($2{\sim}8$), and 6.9($4{\sim}8$). The total UCLA score was an average of 21.7($12{\sim}26$). Patients' the modified UCLA ratings were as follows: Excellent: 3, Good: 6, and Poor: 1. The patient with the poor outcome was the one who had also sustained the neurovascular injury. Patient's subjective satisfaction rating were as follows: Excellent: 2, Good: 7, and Poor: 1. Conclusion: Based on short term follow-up results, this study indicates that hemiarthroplasty is the treatment of choice for proximal humeral fractures on which it would be difficult to perform open reduction and internal fixation. Hemiarthroplasty is a useful treatment modality to prevent shoulder stiffness and to allow daily living tasks in elderly patients. However, restoration of muscle power and range of joint motion were not recovered satisfactorily.

• Clinics in Shoulder and Elbow
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• v.12 no.2
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• pp.189-198
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• 2009

Purpose: We wanted to evaluate the clinical results of the Latarjet procedure for treating anterior shoulder instability combined with a glenoid bone defect. Materials and Methods: Between Oct. 2006 and May. 2007, fourteen patients underwent a Latarjet operation to treat their anterior shoulder instability combined with a glenoid bone defect. The mean follow-up period was 15 months (range: 12 to 19 months), and the average age at the time of surgery was 29.9-years-old (range: 19 to 44 years). There were 13 males and 1 female. Eight patients exhibited involvement of the right shoulder. The dominant arm was involved in 8 patients. Six patients had undergone a previous arthroscopic Bankart repair before their Latarjet operation and 2 patients had a history of seizure. Results: The average Rowe score improved from 51.8 to 80.2 with 9 excellent, 4 good, and 1 fair results. The average Korean shoulder score for instability improved from 61.6 to 82.1 postoperatively. The active forward flexion and external rotation at the side of the involved shoulder was an average of $8^{\circ}$ and $16^{\circ}$ less than that of the uninvolved shoulder. The muscle strength of the involved shoulder measured 78.7% in forward flexion and 82.5% in external rotation, as compared with that of the uninvolved shoulder. There was 1 case of dislocation, 1 transient subluxation, 2 fibrotic unions, 1 resorption of the transferred coracoid process, 1 intraoperative broken bone, 1 transient musculocutaneous nerve injury and 1 case of stiffness. Conclusion: The Latarjet procedure for treating anterior shoulder instability combined with a significant glenoid defect effectively restores function and stability through extending the articular arc at the expense of external rotation. We should be cautious to avoid or detect complications when performing coracoid transfer.