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This study investigated a screening method for assessing driving ability in participants aged ≥65 years, focusing on physical function, specifically handgrip strength (HGS). Quantitative validation analysis revealed a negative correlation between HGS and age and a weak positive correlation between rate of change in HGS and driving simulator score change. The accident rate was slightly higher among individuals with low HGS, though further validation is necessary. Additionally, qualitative validation highlighted individual differences influenced by exercise frequency and social participation. Consequently, we recommend that evaluation methods consider these individual variations, especially when assessing driving ability in individuals with lower HGS.

As Japan faces a super-aging society, the increasing number of elderly people who are bedridden due to fall fractures has become a major social issue. Hip protectors have, thus, been proposed to prevent femoral fractures in cases of tumbling or falling; however, they are not widely used because the tightness of the equipment and the hassle of wearing it. In recent years, flooring materials with high buffer performance have been attracting special attention in the prevention of bone fractures in cases of tumbling or falling. So far, however, the “floor hardness test,” which is an evaluation method for cephalopathy (concussion of the brain), is the only risk assessment method for injury risks caused by flooring materials, and no such evaluation method is available for femoral fracture risks. Therefore, we fabricated a test instrument (pendulum tester) that reproduces the load that the femur received at the point of falling on the floor and developed a mechanism to assess fracture risks with high accuracy on the basis of the measured load. The pendulum tester is characterized by the following features: (1) has an impactor simulating the shape of the femoral region (made using the femoral computed tomography image of the elderly as a reference) and (2) has a dummy skin reproducing the buffering performance of human soft tissue. On conducting fracture risk assessment of four types of commercially marketed flooring materials using the pendulum tester, we found that the merits and demerits of the safety vary greatly by comparing with the evaluation results of the floor hardness test. The above-mentioned results show that an appropriate flooring material evaluation method should be chosen depending on the lesion site and type of injury.

Abstract The present study proposes an advanced force display control system for a surgical training simulator with virtual reality. In oral and orthopedic surgeries, a surgeon uses a chisel and mallet for chiseling and cutting hard tissue. To enable the representation of force sensation for the chiseling operation in a virtual training simulator, the force display device has been constructed with the ball-screw mechanism to obtain high stiffness. In addition, two-degrees-of-freedom (2DOF) admittance control has been used to react instantaneously to the impactive force caused by pounding with the mallet. The virtual chiseling operation was realized by the force display device with a single axis in the previous studies. In the current study, we propose the design procedure for the force display control system with the 2DOF admittance control approach to virtual operation in three-dimensional space. Furthermore, we propose the design method for the PD controller with imperfect derivative using frequency characteristics for the 2DOF admittance control system. The efficacy of the proposed control system is verified through the virtual experience from manipulating the chisel using the developed force display device in the current study.

Sagittal split ramus osteotomy is the most commonly performed for jaw deformity patients in oral and maxillofacial surgery (OMS). In recent years, virtual reality-based surgical training simulators have been developed for reducing the cost of simulated bone, however, effective assistance methods for improving surgical skills have not been well studied. Therefore, the purpose of this study is to develop a manipulation assistance method for surgical training simulator with haptic rendering. The surgical training simulator system is composed of three modules: pre-processing module, interactive surgical training module, and evaluation module. In this paper, we newly implement the pre-processing module for correct answer data generating method, interactive surgical training module for enable users to feel the unique reaction force including cortical bone and cancellous bone, and improve the evaluation module for correct answer data. In the evaluation experiments, 4 testees of surgeons and 4 testees of engineering students performed the surgical training for 1 jaw deformity patient. The training consisted of 3 sets of 5 repetitions. As the results, it was confirmed that our surgical training simulator has the ability to simulate actual surgery from the trials of surgeons. It was also confirmed that bone drilling technics of students had improved by repeating trials. These showed the usefulness of our surgical training simulator. Future work will include additional force assistance and graphic stereoscopy with head-mounted-display.

Background. Transcatheter closure of patent ductus arteriosus (TC-PDA), conventionally guided by aortography, has become the standard treatment of this disease. The purposes of this study were to evaluate whether intracardiac echocardiography (ICE) may be used for measuring PDA size and be used as a guide for TC-PDA. Methods. This study had 2 phases. In phase 1, we compared the measurements of PDA size: pulmonary artery side diameter (PA-D), length, and aortic side diameter (Ao-D) of PDA, as measured by ICE with those measured by aortography or cardiac computed tomography (AoG/CCT) in 23 patients who underwent TC-PDA. In phase 2, we compared the demographics, fluoroscopic time, contrast volume, and complications of the TC-PDAs between 10 adult patients with ICE guidance and 16 without it. Results. In phase 1, we found great correlation and agreement between ICE and AoG/CCT in PA-D (r = 0.985, bias −0.077 to 0.224), but moderate to poor correlation and agreement in length (r = 0.653, bias −0.491 to 3.065) and Ao-D (r = 0.704, bias 0.738 to 4.732), respectively. Nevertheless, all patients underwent successful TC-PDA with ICE guidance that allowed us to continuously monitor the whole process. In phase 2, TC-PDA required a significantly lower contrast volume with ICE guidance than without it, and there was no significant difference in the remaining variables between the 2 groups. Conclusion. ICE is comparable to AoG/CCT in providing accurate PA-D of the PDA and may be a safe alternative to guide TC-PDA as compared to conventional aortography.

The present paper describes a method for 3-dimensional (3D) automated preoperative planning of the femoral component (stem) in total hip arthroplasty (THA). Stem planning is formulated as a problem to determine the optimal parameters of position, rotation, and stem size, based on 3D surface models of host bone reconstructed from CT images, which includes the femur and femoral canal. An objective function that represents the fitness between the femoral canal and stem surfaces is defined. We also defined positional and rotational constraints derived from previous studies on femoral anatomy. Maximization is performed by the Powell method using initial values equally sampled within the possible solution space. We obtained parameters that maximize the objective function by exhaustive adjustment of the parameters. We applied the proposed method to 17 cases, and the proposed method was experimentally evaluated according to differences between planning results of the automated system and those of an experienced surgeon. Preoperative planning was also performed by a surgeon to evaluate performance of the automated system. The difference in stem size was less than 1 size in all cases, and the surgeon agreed with the planning results of the proposed method in 14 cases. In those 14 cases, mean errors of position and orientation were 3.2 mm and 4.6 deg., respectively. The proposed method thus appears applicable in preoperative planning of the stem.

Various transcatheter interventions for the right ventricular outflow tract (RVOT) have been introduced and developed in recent decades. Transcatheter pulmonary valve perforation was first introduced in the 1990s. Radiofrequency wire perforation has been the approach of choice for membranous pulmonary atresia in newborns, with high success rates, although complication rates remain relatively common. Stenting of the RVOT is a novel palliative treatment that may improve hemodynamics in neonatal patients with reduced pulmonary blood flow and RVOT obstruction. Whether this option is superior to other surgical palliative strategies or early primary repair of tetralogy of Fallot remains unclear. Transcatheter pulmonary valve replacement has been one of the biggest innovations in the last two decades. With the success of the Melody and SAPIEN valves, this technique has evolved into the gold standard therapy for RVOT abnormalities with excellent procedural safety and efficacy. Challenges remain in managing the wide heterogeneity of postoperative lesions seen in RVOT, and various technical modifications, such as pre-stenting, valve ring modification, or development of self-expanding systems, have been made. Recent large studies have revealed outcomes comparable to those of surgery, with less morbidity. Further experience and multicenter studies and registries to compare the outcomes of various strategies are necessary, with the ultimate goal of a single-step, minimally invasive approach offering the best longer-term anatomical and physiological results. [ABSTRACT FROM AUTHOR]