Dummy Torso Research Articles

뒷좌석 안전벨트 D-ring 위치에 따른 인체 더미의 어깨 이동량에 관한 설계개선 연구

뒷좌석 안전벨트 D-ring 위치에 따른 인체 더미의 어깨 이동량에 관한 설계개선 연구

Billing Implications of Emergency Medicine Resident Physicians’ Laceration Length Estimates

CONTEXTLacerations are a common occurrence in urgent care and emergency room settings. The types of lacerations repaired in these settings range from superficial and linear to deep and stellate. Healthcare professionals are required to describe these wounds in documentation and part of that description is length. In a busy clinical setting, many providers use a visual estimation of wound length for documentation. The purpose of this exploratory pilot study was to systematically examine the factors (e.g., sex, residency year, prior laceration training) associated with overall accuracy of five laceration length estimates made on a series of five identically-marked linear dummy torso sutured lacerations by a convenience sample of Emergency Medicine (EM) resident physicians. Before the study, the authors hypothesized that laceration estimates from later-year residents and/or those with more prior laceration training would be more accurate.METHODSThe EM residents who attended a statewide educational session were encouraged to participate in the study by independently entering information concerning their a) personal characteristics, and b) five laceration length estimates from five dummy torso sutured lacerations onto hard copy forms during break and lunch periods of the daylong conference. The use of any types of measurement devices was prohibited.RESULTSA total non-probability convenience sample of 107 participants (93 EM resident physicians and 14 medical student attendees) from 14 different Michigan-based EM residency programs completed a 10-item survey during the educational conference. Results for both composite and individual actual-to-estimated (AE) laceration differences varied widely within the sample, with up to 58.9% of laceration over estimates hypothetically having resulted in overbilling of payers for the laceration repair.CONCLUSIONSThe considerable range in laceration estimates obtained from these EM clinicians indicate the complexity of attempting to estimate lacerations without measuring devices, as well as the potential for over-billing under such conditions. Larger resident samples recording laceration length estimates, with testing of potential interaction effects on AE patterns, are needed in the future to provide additional evidence concerning this aspect of EM billing.

Countermeasures to mitigate head and neck injuries to toddlers in frontal and lateral vehicle crash conditions

This study focuses on methods to reduce injuries, specifically in the head and neck region, sustained by children seated in forward-facing child safety seats during a vehicle crash. A fully deformable finite element model (FEM) of a child restraint seat incorporating a Hybrid III 3-year-old dummy has previously been developed which has been validated for frontal impacts under CMVSS 208 and FMVSS 213 testing conditions, and near-side impacts under ANPRM (FMVSS 213) norms. Observations from this previous work have illustrated higher values of neck forces and moments sustained by the dummy's neck. The main objective of this research was to develop a head and neck restraining device in order to limit the forward and lateral head movement/rotation of the child. The head and neck safety device comprised two parts, namely the collar and the tether. The collar was restrained to the dummy's torso with the seatbelt and the tether was constrained to the dummy's head. In addition, the effect of using a cross-shaped rigid ISOFIX system was also investigated. Three numerical models were developed incorporating a Hybrid III 3-year-old dummy, Q3/Q3s child dummies and a child FEM. Numerical simulations were completed in frontal, near-side and a 45° impact situation in accordance with the FMVSS 213 norms in the absence and presence of the head and neck safety device, for both the flexible LATCH and the cross-shaped rigid ISOFIX system. Evaluation of injury criteria based on the quantitative analysis of the simulations yielded that the head and neck device in conjunction with the rigid ISOFIX system was effective in reducing the resultant upper neck forces by approximately 40 to 75% for all the child models under different impact conditions. In addition, the head injury criterion was observed to be reduced by approximately 45 to 65% for all the impact conditions. Presence of the head and neck device effectively reduced the head excursions for all the impact conditions. In addition, the cross-shaped rigid ISOFIX further decreased the CRS displacement in both the forward and lateral directions. The forward and lateral displacement of the centre of mass of the head was observed to be reduced by approximately 30 to 50% for different impact conditions. Greater amount of bending in both the lateral and forward directions was observed for the Q3/Q3s dummies and the child FE model. This can be attributed to lower degree of stiffness and geometrical differences in the Q3/Q3s dummy's neck, which make the neck more flexible.

Reconstruction of Crashes Involving Injured Child Occupants: The Risk of Serious Injuries Associated with Sub-Optimal Restraint Use May Be Reduced by Better Controlling Occupant Kinematics

Objective. To determine whether injuries to sub-optimally restrained child occupants in real-world crashes were likely to be preventable by alternative restraint usage practices and to assess the usefulness of crash reconstruction for exploring injury mechanisms in child occupants. Methods. Real-world crashes in which child occupants sustained significant injuries were reconstructed on a laboratory crash sled using the Hybrid III family of child dummies. Alternative restraint scenarios and cases in which children were not seriously injured were also simulated to compare dummy kinematics and dynamic responses in optimal restraint configurations. Results. Restraint misuse was associated with greater motion of the dummy torso and head during crashes, often allowing contact between the child and the vehicle interior, resulting in injury. Poor pre-crash posture for a child inappropriately restrained in an adult belt appeared to worsen the geometry of the sash (shoulder) belt, resulting in a cervical injury due to direct interaction with the belt. Dynamic dummy data did not appear to discriminate between injury and non-injury cases. Conclusions. Dummy kinematics suggest that injuries in which inappropriate use and misuse were a factor were less likely if the most appropriate restraint was used correctly. Adequately controlling the head and upper body of the child occupant was seen to prevent undesirable interactions with the vehicle interior and restraint system, which were associated with injury in the real world. Neck forces and moments and injury criteria calculated from these did not predict injury reliably.

Computer-based training in two-dimensional echocardiography using an echocardiography simulator

Two-dimensional (2D) echocardiography is a user-dependent technique that poses some inherent problems to the beginner. The first problem for beginners is spatial orientation, especially the orientation of the scan plane in reference to the 3-dimensional (3D) geometry of the heart. The second problem for beginners is steering of the ultrasound probe. We have designed a simulator to teach these skills. On a computer screen a side-by-side presentation of a 3D virtual reality scene on the right side and a 2D echocardiographic view on the left side is given. The virtual scene consists of a 3D heart and an ultrasound probe with scan plane. The 2D echocardiographic image is calculated from 3D echocardiographic data sets that are registered with the heart model to achieve spatial and temporal congruency. The displayed 2D echocardiographic image is defined and controlled by the orientation of the virtual scan plane. To teach hand-eye coordination we equipped a dummy transducer with a 3D tracking system and placed it on a dummy torso. We have evaluated the usability of the simulator in an introductory course for final-year medical students. The simulator was graded realistic and easy to use. According to a subjective self-assessment by a standardized questionnaire the aforementioned skills were imparted effectively.

A Methodology for Assessing Blast Protection in Explosive Ordnance Disposal Bomb Suits

To reduce human casualties associated with explosive ordnance disposal, a wide range of protective wear has been designed to shield against the blast effects of improvised explosive devices and munitions. In this study, 4 commercially available bomb suits, representing a range of materials and armor masses, were evaluated against 0.227 and 0.567 kg of spherical C-4 explosives to determine the level of protection offered to the head, neck, and thorax.A Hybrid III dummy, an instrumented human surrogate [1], was tested with and without protection from the 4 commercially available bomb suits. 20 tests with the dummy torso mounted to simulate a kneeling position were performed to confirm repeatability and robustness of the dummies, as well as to evaluate the 4 suits. Correlations between injury risk assessments based on past human or animal injury model data and various parameters such as bomb suit mass, projected area, and dummy coverage area were drawn.

Differences in the intracranial pressure caused by a ‘blow’ and/or a ‘fall’ — An experimental study using physical models of the head and neck

In cases of a severe head injury caused by a fall, coup contusions are either absent or very minor, in contrast to presence of extensive contre-coup damage. In cases of a severe blow to a head, however, the reverse occurs, with contre-coup lesions a rarity and coup damage extensive. To investigate this further, head injuries caused by a ‘blow’ or a ‘fall’ have been studied, using physical human models of the head and neck, both filled with distilled, degassed water and fixed onto a dummy torso. An impact of a constant magnitude was applied to the midoccipital region in ‘blow’ and ‘fall’ experiments, and the acceleration of the head and changes in the intracranial pressure were measured, with the resulting data analyzed by a computer. In both experiments, the peak amplitude of the acceleration pulse were almost the same. Similarly, the intracranial pressure curve at the impact site consisted of a positive pulse that hardly differed, nor did the peak amplitude of that pulse vary significantly. In the ‘blow’ experiment, however, the intracranial pressure curve at the site opposite the impact consisted of a negative pulse, whereas in the ‘fall’ experiment, the intracranial pressure recorded at the same area was negative but of a longer duration, with an absolute value that was slightly greater. Our results indicate that an impact to the head triggers a different response in the intracranial space, dependent on whether that impact force was caused by a ‘blow’ or a ‘fall’.