Maintaining balance is a factor critical and integral to our effective physical function as it relates to the normal activities of daily living. Of the “hip strategy”, “stepping strategy” and “ankle strategy”, it is known and accepted that the “ankle strategy” is the first activated parameter to assist in the maintenance of balance in motor output. However, few studies actually evaluated or assessed the precise attributes of “ankle strategy” in relation to any therapeutic effort tocorrect and/or rehabilitate from physical imbalance caused by dynamic tilting perturbation. The aim of the study was to identify precise characteristics of the “ankle strategy” as they respond to dynamic tilting perturbations. Seven healthy male (aged 25.5 ± 1.7 years, average height of 173.9 ± 6.4 cm, average body mass of 71.3 ± 6.5 kg) were recruited to participate. The ankle joint motions were subjected to eight dynamic tilting perturbations generated by the customized tilting perturbation simulator, and the responses were measured by 3D motion capture system. Concurrently, foot pressure distribution and the corresponding centers of pressure (COP) trajectory were measured by a pressure measuring system, and the four main muscles’ activations related to the ankle joint motions were measured by wireless electromyogram system.

Recently, a Total Ankle Arthroplasty (TAA) has been commonly used when no other options are available for patients with severe arthritis at the ankle joint. But bone resorption, aseptic loosening, instability, malalignment and fractures are generally known as the main reasons of TAA failures. Those TAA which have been designed up until now are generally based on the morphological and kinesiological characteristics of the ankle joint. They are adjusted by the ankle joint size of Westerners, although both the morphological and mechanical (strength) characteristics of the ankle joints of Asian are important in the development of a TAA suitable to Asians. Little information about the morphological and mechanical characteristics of the ankle joint of Asians is available for the development of a TAA suitable to Asians. The purpose of this study was, therefore, to analyze the morphological and mechanical characteristics of the ankle joints of Asians. Computed tomography data obtained from 50 patients (mean age: 64.14 ± 9.34 years) were analyzed.

The aim of this study was to investigate, through a longitudinal tracking, whether gender influences morphological characteristics on trabeucular bone of tibia during unloading. 12 male and 15 female ICR mice at 6 week of age were used and randomly allocated into two groups in each gender; unloading and normal group, respectively. Mice in unloading group were operated on denervation (sciatic neurectomy). The tibiae were scanned by using in vivo micro-computed tomography (micro-CT) at 0 day (before denervation) and after 14 days. Structural parameters and BMD on tibia were measured. In female, BV/TV (65%), Tb.Th (5%), Tb.N (61%) and BMD (62%) were significantly decreased and BS/BV (17%), Tb.Sp (54%), SMI (19%) and Tb.Pf (75%) were significantly increased after unloading (p＜0.05). In male, BV/TV (1%) and Tb.N (10%) were significantly decreased and SMI (5%) was significantly increased after unloading (p＜0.05). In addition, trabeuclar bone loss of female was significantly bigger than that of male (p＜0.05). These results indicated that effects of unloading on trabecular bone in growing mice might have difference between female and male, although unloading result in loss of quantity and quality on trabecular bone both female and male.

Pharmacotherapy was mainly used to treat osteoporosis. However, some researches showed that pharmacotherapy could induce unexpected adverse effects. Some studies showed that whole body vibration affected beneficially osteoporosis. This paper studied the effect of whole body vibration for osteoporosis compared with the effect of pharmacotherapy.
10 female rats were used and allocated into 4 group, CON, SHAM, DRUG, and WHY. Rats except SHAM group were ovariectomised to induce osteoporosis. Rats in WHV group were stimulated in whole body vibration at magnitude of 1㎜^peak-peak and frequency 45㎐, for 8 weeks (30 min/day, 5 days/week). Rat in DRGU group was orally administered the Actonel (0.58㎎/㎏), for 8 weeks (5days/week). The 4^th lumbar in rats were scanned at a resolution of 35㎛ at baseline, before stimulation, and 8 weeks after stimulation by In-vivo micro computed tomography. For detecting and tracking changes of biomechanical characteristics (morphological and mechanical characteristics) in lumbar trabecuar bone of rats, structural parameters were measured and calculated from acquiring images and finite element analysis was performed.
In the results, loss of quantity and change of structure of trabecular bone in WBV group were smaller than those in both CON and SHAM groups. In addition, mechanical strength in WBV group was stronger than that in both CON and SHAM groups. In contrast, biomechanical characteristics in WBV group were similar with those in DRUG group.
These results showed that reasonable whole body vibration was likely to treat osteoporosis and be substituted partly for drug treatment.

This study investigated biomechanical response through the 3-dimensional virtual skeletal model developed and validated. Ten male subjects in standing posture were exposed to whole body vibrations and measured acceleration on anatomical of interest (head, 7th cervical, 10th thoracic, 4th lumbar, knee joint and bottom of the vibrator). Three dimensional virtual skeletal model and vibration machine were created by using BRG LifeMOD and MSC. ADAMS. The results of forward dynamic analysis were compared with results of experiment. The results showed that the accuracy of developed model was 73.2±19.2% for all conditions.

The disaster from functional gastrointestinal disorders(FGID) has detrimental impact on the quality of life of the affected population. There are, however, rare diagnostic methods for FGID. Our research group identified recently that the gastrointestinal tract well of the patients with FGID became more rigid than that of healthy people when palpating the abdominal regions overlaying the gastrointestinal tract. The objective of the current study is, therefore, to identify feasibility of a diagnostic system for FGID based on ultrasound technique, which can quantify the characteristics above. Two-dimensional finite difference(FD) models(one normal and two rigid models) were developed to analyze the reflective characteristic(displacement) on each soft-tissue layer responded after application of ultrasound signals. Based on the results from FD analysis, the ultrasound system for diagnosis of the FGID was developed and clinically tested via application of it to 40 human subjects with/without FGID who were assigned to Normal and Patient Groups. The results from FD analysis showed that the maximum displacement amplitude in the rigid models(0.12 and 0.16) at the interface between the fat and muscle layers was explicitly less than that in the normal model(0.29). The results from actual specimens showed that the maximum amplitude of the ultrasound reflective signal in the rigid models(0.2±0.1Vp-p) at the interface between the fat and muscle layers was explicitly higher than that in the normal model(0.1±0.0Vp-p). Clinical tests using our customized ultrasound system showed that the maximum amplitudes of the ultrasound reflective signals near to the gastrointestinal tract well for the patient group(2.6±0.3Vp-p) were generally higher than those in normal group(0.1±0.2Vp-p). These findings suggest that our customized ultrasound system using the ultrasound reflective signal may be helpful to the diagnosis of the FGID.