ABSTRACT
The purpose of this study was to determine the relationship in prepubertal children between lower limb muscle thickness, a quantitative index of lower limb muscle, and sprint motion, in order to clarify the effects of muscle mass development on sprint motion as well as differences in these effects due to sex and muscle location. Participants comprised 41 children in 8year-old (21 boys, 20 girls) in good health attending an elementary school in the city of Kitakyushu. Muscle thickness of the anterior thigh (MTa), posterior thigh (MTp), and calf (MTC) were measured using B-mode ultrasonography. Sprint abilities (sprint speed, stride length, and step frequency), kinematic indices relating to sprint motion and ground reaction force were also measured. Pearson product-moment correlation coefficients were calculated to determine relationships between measured variables. Effects of height and weight were eliminated, and stepwise multiple linear regression analysis was performed, using stride length and step frequency as dependent variables, and kinematic indices and ground reaction force as independent variables. In boys, posterior thigh muscle thickness and calf muscle thickness showed significant simple correlations with flying time/support time (FT/ST), which was selected as an explanatory variable for step frequency. However, no significant relationship was found between step frequency and sprint speed. The conclusion of these findings is that developing lower limb muscle mass affects sprint motion in 8-year-old boys, but does not directly lead to improved sprint speed. In girls, a significant relationship was found between posterior thigh muscle thickness and maximal leg swing velocity during the support phase (ωL), which was selected as an explanatory variable for step frequency, and a significant relationship was found between step frequency and sprint speed. Unlike boys, developing lower limb muscle mass in 8-year-old girls influences step frequency and is closely connected to sprint speed.
ABSTRACT
The purpose of this study was to clarify the effects of lower limb muscle mass growth on sprinting ability in children aged 3 to 8 years. The subjects were 514 unimpaired children (266 boys and 248 girls). We measured their lower limb muscle thickness (anterior thigh: MTa, posterior thigh: MTp, and calf: MTC) and 25 meter sprinting time. Muscle thickness was measured using a B-mode ultrasound diagnostic imaging unit. From the 25 meter sprint, we measured the following characteristics in relation to sprinting ability: results, maximum velocity, stride and pitch. The results revealed that sprinting ability significantly correlated with MTp and MTC in both boys and girls. This suggests that, in addition to morphological development, lower limb muscle mass growth contributes to an increase in stride (m/step) and affects sprinting ability during the period from infancy to early childhood. However, no relationship was seen between sprinting ability and anthropometric characteristics (body height and mass) or lower limb muscle thickness among 8-year-old boys. It is possible that lower limb muscle quality and power as well as improvement in elements such as sprinting movement have a stronger influence on sprinting ability than morphological elements such as physique and muscle mass in boys around that age. In contrast, a significant relationship was seen between lower limb muscle thickness and sprinting ability in girls of all age groups, suggesting that, unlike boys, innate lower limb muscle mass influences sprinting ability for girls.
ABSTRACT
The purpose of this study was to compare age and gender differences of lower limb muscle thickness among healthy young children. Five hundred and sixty-one healthy young children aged 3 to 8 years old (284 boys and 277 girls) participated in this study. Anterior thigh, posterior thigh, and calf muscle thicknesses (MTa, MTp, MC) were determined using a B-mode ultrasound. The thickness of each muscle increased significantly as age increased, except in the MTa in the 5-year-old boys' group. A significantly main effect was found in MTa, and there was a higher value in girls than boys, except in the 4-year-old group. A significant age × gender interaction was also observed in MTa, with higher values found in boys than girls, except in the 3- and 5-year-old groups. There was no significant gender different in MC. In addition to the Mt/Tmt ratio, the ratio of each muscle thickness to the total amount of MTa, MTp, and MC was calculated. As a result, in girls, the Mt/Tmt ratio remained constant as age increased in all muscles. On the other hand, in boys, MTa decreased and MTp increased as age increased. From these results, it was suggested that gender differences exist in lower limb muscles thickness among healthy young children aged between 3 and 8 years old. It was also suggested that the muscle development of MTa and MTp was different in boys, while lower limb muscle development in girls stayed constant.
ABSTRACT
We describe a 77-year-old woman with severe aortic stenosis, porcelain aorta and coronary artery disease, who underwent apicoaortic bypass with coronary artery bypass grafting. The patient, who had a history of aortitis syndrome had dyspnea. Cardiac echocardiography showed severe aortic valve stenosis (aortic valve pressure gradient (max/mean) = 115/74.4 mmHg, aortic valve area = 0.48 cm<sup>2</sup>). Coronary angiography showed severe stenosis of right coronary artery orifice (#1.90%) . Computed tomography showed severe calcification of the thoracic aorta and surgical manipulation for ascending aorta was impossible. We did not perform ordinary aortic valve replacement. Instead, apicoaortic bypass with coronary artery bypass grafting was performed. We approached by a left anterolateral thoracotomy at the 6th intercostal level. Apicoaortic valved conduit (valved graft : Edwards Prima Plus Stentless Porcine Bioprosthesis 19 mm + UBE woven graft 16 mm) was implanted. Saphenous vein graft was harvested and coronary bypass grafting (valved conduit-#4AV) was performed in the same operative field. Postoperative cine MRI showed that most of the cardiac stroke volume flowed through the conduit (44.4 ml/beat, 92.3%), with the flow via the aortic valve accounting for 3.69 ml/beat, 7.7%. Postoperative enhanced CT showed that the coronary artery bypass graft was patent. Apicoaortic bypass is a good surgical option for aortic stenosis with severe calcification aorta and coronary artery bypass grafting can also be performed in the same view.
ABSTRACT
We describe a novel method for repeat median sternotomy. We have successfully used ‘finger’ lifting resternotomy technique and achieved zero major cardiovascular injury/catastrophic hemorrhage events at reoperation. After general anesthesia, all patients were placed in the supine position and two external defibrillator pads were placed on the chest wall. We perform a median skin and subcutaneous incision along the previous sternotomy incision extending 3 cm distal to the sternum. The sternal wires that had been used for the previous closure were left in place but untied. Using a long electric cautery, right thoracotomy was performed under the right costal arch approach. Then, the operator could approximate the sternal wires in the retro-sternal space. At the same time, the operator could confirm the retro-sternal adhesion status which by touching with a finger. Resternotomy was performed using an oscillating saw pointed toward the operator's finger, which allowed safe re-median sternotomy from the lower to the upper part of the sternum. This technique of finger-lifting resternotomy has been employed in 50 cardiovascular reoperations and resulted in 0 incident of major cardiac injury or catastrophic hemorrhage. The finger-lifting resternotomy technique is safe and simple in reoperation procedures and yield excellent early outcomes.
ABSTRACT
Thoracic graft infection is a serious complication and has high mortality. We report a case of successful treatment of graft infection after ascending thoracic aortic reconstruction. A 66-year-old woman underwent surgery for DeBakey type I aortic dissection in June 2007. The ascending aorta was replaced with a prosthetic graft. Although her postoperative course was complicated with Methicillin-resistant <i>Staphylococcus aureus</i> (MRSA) mediastinitis, the infection was conservatively controlled by mediastinal lavage and antibiotics. However, she was readmitted in April 2008 due to lumbar pain and high fever, and was diagnosed with infectious spondylitis. Lumbar plastic surgery was performed. During hospitalization, she underwent total systemic examination. The results indicated aneurysm of the ascending aorta. MRSA was detected from culture fluid of her blood. Taken together, the presence of an infected aortic aneurysm was considered possible. Consequently, reconstruction of the ascending aorta using two allografts was performed after removing the prosthetic graft. The postoperative course was uneventful, and she was discharged on the 71st postoperative day. The patient continues to thrive 9 months after the operation. This case of an infected aortic aneurysm repaired with the use of allografts will be reported together with references to the literature.
ABSTRACT
We report a case of chronic localized thoracoabdominal aortic dissection with an entry located just above the celiac artery which was successfully treated by patch aortoplasty. The patient was a 55-year-old man who complained of abdominal and back pain. CT scan and angiography showed a localized thoracoabdominal aortic dissection the entry of which was located just above the celiac artery. The patient underwent resection of the aneurysm and patch aortoplasty with the aid of a femoro-femoral bypass. The postoperative course was uneventful. Localized thoracoabdominal aortic dissection has been reported in only 5 cases, including our case, in the Japanese literature.
ABSTRACT
To clarify changes in body temperature during endurance exercise in patients with spinal cord injury (SCI), we measured tympanic temperature (Tty) and skin temperature in the head, arm, chest, thigh, shin and calf in 5 patients with SCI (T6-T 12) and 7 normal controls during 30 minutes arm cranking exercise (20 watts) from 10 minutes before the initiation of exercise until 10 minutes after the termination of exercise in an artificial climate room at a temperature of about 25°C with a relative humidity of about 50%. The Tty in the SCI group was lower than that in the control group from 10 minutes before the initiation of exercise to 10 minutes after the termination of exercise with a significant difference only at the initiation of exercise. The difference in Tty slightly decreased with continuation of exercise. The Tty in the SCI group at rest was 36.05-37.15°C. Four patients in this group showed a decrease of 0.04-0.12°C in the early stage and an increase of 0.66°C±0.19 (mean±SD) at the end of exercise over the value at the initiation of exercise.<BR>The skin temperature was lower in the SCI group than in the control group in all sites excluding the arm. Significant differences were observed in the head in the early stage of exercise and after exercise, in the chest from 10 minutes before the initiation of exercise to 5 minutes after the termination of exercise, in the thigh from 10 minutes before the initiation of exercise to 10 minutes after the termination of exercise, in the shin 10 minutes and 5 minutes before the initiation of exercise, and in the calf from before to 15 minutes after the initiation of exercise. In the SCI group, marked individual differences were observed in the skin temperatures in the thigh, shin, and calf, suggesting specificity of the skin temperature response in and near the paralysis area.<BR>Results in Tty in this study suggested no heat retention in the SCI patients. Therefore, the risk for heat disorders seems to be low during moderate or mild exercise under moderate temperature environment at a temperature of about 25°C with a relative humidity of about 50% even when the skin temperature is low, and thermolysis is not marked.