Twenty-four male university baseball players were each requested to throw a baseball, and filmed using the direct linear transformation method of three-dimensional (3D) videography. 3 D coordinates of landmarks were obtained. Resultant joint forces and resultant joint torques in the wrists, elbows, shoulders, neck, and upper torso joints were calculated using the inverse dynamics method. The mechanical powers caused by the resultant joint forces (joint force power) and by the resultant joint torques (joint torque power) of each segment were calculated, and the mechanical work was also obtained by integrating the joint torque powers with time. Peak values of energies of the upper torso, upper arm, forearm, hand, and ball appeared in sequence from the proximal segment to the distal segment. The joint force powers in any segment were markedly larger than the joint torque powers. Little joint torque power was produced in the wrist throughout the throwing motion. The negative joint force power and joint torque power at the proximal end of the upper torso were rapidly increased immediately after the foot contact stride. It was clarified that the appearance of the large energies in the distal throwing arm segments during the final phase of throwing motion were caused mainly by transfer of the energies produced by the motions of the torso and shoulder joints. This paper discusses the mechanical energy flows of the upper torso and upper limb segments during the motion of baseball throwing.

This study was designed to clarify the causes of throwing injuries of the elbow and shoulder joints in baseball. Five varsity-skilled baseball players without pain in the elbow and shoulder joints were subjects for this study. They were fixed to a chair and asked to throw a baseball using three different throwing arm movements (T₀, T₄₅, and T₉₀) . These movements were filmed using three-dimensional DLT videography. Linked rigid-body segment inverse dynamics were then employed to determine resultant joint force and torque at the elbow and shoulder joints. Peak varus torque at the elbow joint for T₉₀ was less than for the other movements during the acceleration phase. In the follow-through phase, however, a large anterior shear force (70 N) at the elbow, for elbow extension, was present for T₉₀. These results indicate that T₉₀ was a high risk movement which leads to extension injuries rather than medial tension injuries. After the ball release, a large superior shear force (118 N) at the shoulder joint was present in all movements. This superior force may result from the subacromial impingement syndrome, except for critical zones of impingement caused by the different throwing arm movements. These findings suggest that the mechanisms of throwing arm injuries are closely related to differences in throwing arm movements.

A 51-year-old man with osteogenesis imperfecta and who had aortic regurgitation was admitted to our hospital for aortic valve replacement. His height was 146cm and his weight was 49kg. The patient had suffered from bone fractures several times since childhood. Bone deformity, blue sclera and his status were clinically indicative of osteogenesis imperfecta. Aortic valve replacement with a 25mm SJM^® prosthetic valve was successfully performed for aortic valve insufficiency and slight annulo-aortic ectasia. Soft tissues and the sternum were fragile. Pathological examination (Elastica-Masson stain) of the aortic valve and left ventricular wall revealed a loss of fibrous tissues and remarkable thickening due to elastic fibers. The patient was discharged 31 days after surgery. Osteogenesis imperfecta is one of the collagen diseases caused by gene abnormality, in which fragile bones are easily fractured. Cardiovascular disease is rarely associated with it and the surgery-related mortality rate is reported to be approximately 30%, due to bleeding.

Central giant cell lesions are rare, benign, osteolytic, pseudocystic, solitary, localized lesions that are common in the skeletal structure, but less so in the maxillofacial region. Furthermore, to perform panoramic radiography and cone-beam computed tomography, it is necessary to prepare patients properly and to position their heads carefully. However, this can be difficult in pediatric patients, who may be anxious. In this report, we describe the case of a central giant cell lesion of the mandible in a 2-year-old girl that was evaluated with multidetector computed tomography.
Child ; Child, Preschool ; Cone-Beam Computed Tomography ; Female* ; Giant Cells* ; Granuloma, Giant Cell ; Head ; Humans ; Mandible* ; Multidetector Computed Tomography ; Radiography, Panoramic

Computed tomography (CT) and magnetic resonance imaging (MRI) can be useful for the evaluation of palatal lesions, and strain elastography (performed together with intraoral ultrasonography) is a relatively new sonographic imaging modality. This report describes 2 clinical cases in which strain elastography was used to assess palatal tumors in conjunction with intraoral ultrasonography, CT, and MRI. In the first case, diagnosed as a myoepithelioma, the strain was determined to be 0.000% (strain of normal tissue, 0.556%). In the second case, diagnosed as an adenoid cystic carcinoma, the determined strain was 0.000% (strain of normal tissue, 1.077%). Therefore, we conclude that intraoral strain elastography can be useful for evaluating palatal lesions.

BACKGROUND: Management of postprandial hyperglycemia is a key aspect in diabetes treatment. We developed a novel system to measure glucose area under the curve (AUC) using minimally invasive interstitial fluid extraction technology (MIET) for simple monitoring of postprandial glucose excursions. In this study, we evaluated the relationship between our system and continuous glucose monitoring (CGM) by comparing glucose AUC obtained using MIET with that obtained using CGM for a long duration. METHODS: Twenty diabetic inpatients wearing a CGM system were enrolled. For MIET measurement, a plastic microneedle array was applied to the skin as pretreatment, and hydrogels were placed on the pretreated area to collect interstitial fluid. Hydrogels were replaced every 2 or 4 hours and AUC was predicted on the basis of glucose and sodium ion levels. RESULTS: AUC predicted by MIET correlated well with that measured by CGM (r=0.93). Good performances of both consecutive 2- and 4-hour measurements were observed (measurement error: 11.7%±10.2% for 2 hours and 11.1%±7.9% for 4 hours), indicating the possibility of repetitive measurements up to 8 hours. The influence of neither glucose fluctuation nor average glucose level over the measurement accuracy was observed through 8 hours. CONCLUSION: Our system showed good relationship with AUC values from CGM up to 8 hours, indicating that single pretreatment can cover a large portion of glucose excursion in a day. These results indicated possibility of our system to contribute to convenient monitoring of glucose excursions for a long duration.
Area Under Curve* ; Extracellular Fluid ; Glucose* ; Humans ; Hydrogel ; Hydrogels ; Hyperglycemia ; Inpatients ; Plastics ; Skin ; Sodium

Purpose: The purpose of this study was to evaluate the cone-beam computed tomographic (CBCT) imaging and histopathological characteristics of osteoradionecrosis (ORN) and medication-related osteonecrosis of the jaw (MRONJ). Materials and Methods: Ten surgical specimens from segmental mandibulectomy (3 ORN and 7 MRONJ) were analyzed using CBCT. The CBCT parameters were as follows: high-resolution mode (tube voltage, 90.0 kV; tube current, 4.00 mA; rotation time, 16.8 s; field of view, 56 mm×56 mm; thickness, 0.099 mm). Histopathological characteristics were evaluated using histological slides of the surgical specimens. The Pearson chi-square test was used to compare ORN and MRONJ in terms of CBCT findings (internal texture, sequestrum, periosteal reaction and cortical perforation) and histopathological characteristics (necrotic bone, inflammatory cells, reactive bone formation, bacteria, Actinomyces, and osteoclasts). A P value less than 0.05 was considered to indicate statistical significance. Results: MRONJ showed periosteal reaction on CBCT more frequently than ORN (7 of 7 [100%] vs. 0 of 3 [0%], P<0.05). Regarding histopathological characteristics, MRONJ showed osteoclasts more frequently than ORN (6 of 7 [85.7%] vs. 0 of 3 [0%], P<0.05). Conclusion This study evaluated the CBCT imaging and histopathological characteristics of ORN and MRONJ, and the findings suggest that CBCT could be useful for the evaluation of ORN and MRONJ.

Background: Peripheral circulation is often disturbed in patients with connective tissue diseases (CTDs) and its objective evaluation is an important issue. Infrared thermography has been used for the purpose for decades [1]. Raynaud phenomenon (RP) is prevalent in and considerably characteristic of CTDs and we have long noticed colour unevenness among fingers in patients during RP attacks. We hypothesized that temperature unevenness among fingers detected by thermography would be a useful parameter to evaluate peripheral circulation. Objectives: To evaluate temperature unevenness among fingers as a thermographic parameter by comparing it with other parameters validated in previous studies. Methods: Patients who visited our hospital and had been diagnosed as having RP by their attending physicians and underwent thermographic examinations were included and compared with healthy volunteers. Skin temperatures of dorsum of hands at 10 fingers’ nail folds and MCP joints were measured at baseline. Then hands were immersed in 10°C water for 10 seconds. Skin temperatures were measured at 0, 3, 5, 10, 15, 20, and 30 min after immersion. Mean temperature, recovery rate (temperature recovery from immersion/decrease by immersion), and coefficient of variation (standard deviation/mean temperature) of nail fold temperature were calculated. Higher coefficient of variation means temperature among fingers is more uneven. Distal-dorsal difference (DDD: measured by subtracting mean temperature of MCP from that of nail fold) was also calculated and these parameters were compared between the two groups. Receiver operating characteristic (ROC) curve was generated to compare these parameters in terms of their capability of differentiating patients with RP from HCs. Results: Thirty-one patients with RP (10 with primary Raynaud, 11 with systemic sclerosis (SSc), 11 with other CTDs) were included and compared with 25 healthy controls (HCs). Baseline nail fold temperature was significantly lower in patients of RP than in HC (30.8±3.1 °C vs. 33.2±1.8 °C, p=0.0002). Cold-water immersion of hands revealed patients with RP had lower recovery rate, lower DDD, and higher coefficient of variation than did HCs. The differences in these parameters were the most evident at 5 min after immersion (patients with RP vs HCs: recovery rate; 49.6±27.7 vs 71.5±26.8, p=0.004 DDD; -1.4±2.8 vs 0.85±2.7, p=0.0008 coefficient of variation; 0.053±0.024 vs 0.021±0.015, p=1.2x10-6). On the basis of ROC curve analyses for these parameters, coefficient of variation of nail fold temperature most effectively differentiated patients with RP from HCs (Area under the curve; recovery rate: 0.64 DDD: 0.79 coefficient of variation: 0.88). Conclusions: Unevenness of temperature among fingers was the most useful thermographic parameter to evaluate disturbed peripheral circulation.