Fatalities attributed to powered circular saws appear to be vanishingly rare events with highly wounding and rapidly incapacitating effects. When they do occur, they are mainly self-inflicted in nature. We report the suicide committed by a 79-year-old man using a self-made circular table saw. Autopsy confirmed that the man received multiple heterogeneously distributed saw-type impacts to the head and neck resulting in complete amputation of the upper skull and partial beheading. Homemade or modified commercial sawing instruments and the resultant injuries pose a number of forensic challenges starting from the death scene investigation, continuing with technical examinations, and concluding with determining the manner of death. As with all deaths due to sharp force injuries, fatalities involving power tools such as chainsaws, circular, and band saws warrant a high degree of suspicion of criminal activity and require diligence during all phases of the death investigation.

• Klíčová slova
• Amputation, Autopsy, Circular saw, Decapitation, Morphology, Suicide,
• MeSH
• lidé MeSH
• penetrující rány patologie   MeSH
• pitva MeSH
• poranění krku etiologie   patologie   MeSH
• poranění obličeje etiologie   patologie   MeSH
• sebevražda * MeSH
• senioři MeSH
• soudní patologie metody   MeSH
• traumatická amputace patologie   MeSH
• Check Tag
• lidé MeSH
• mužské pohlaví MeSH
• senioři MeSH
• Publikační typ
• časopisecké články MeSH
• kazuistiky MeSH
• přehledy MeSH

A 61-year-old man was found dead in the yard of his house with penetrating injury of the trunk. Initial examination of the body revealed a single penetrating injury on his chest with a collar abrasion-the injury pattern that is similar to a gunshot entry wound or shored exit wound. According to witnesses, the man had cut wooden frames from old windows with a circular saw. X-rays of the torso revealed a contrast object resembling a projectile in the left scapular region. The internal examination disclosed an isolated trunk trauma involving the left lung. In the soft tissue, between the inner edge of the left scapula and thoracic spine, the fragment of a metal nail was found. The autopsy confirmed that the wound on the chest was a non-firearm-related injury. The death of deceased was attributed to massive internal hemorrhage. Further investigation revealed that the pseudo-gunshot wound injury of the trunk of the victim was caused by a fast-flying metal object thrown against the man's trunk from a circular saw while cutting the wooden beams of old windows.

• MeSH
• cizí tělesa diagnostické zobrazování   patologie   MeSH
• diferenciální diagnóza MeSH
• krvácení etiologie   patologie   MeSH
• lidé středního věku MeSH
• lidé MeSH
• penetrující rány etiologie   patologie   MeSH
• poranění hrudníku etiologie   patologie   MeSH
• poškození plic etiologie   patologie   MeSH
• radiografie MeSH
• soudní patologie MeSH
• Check Tag
• lidé středního věku MeSH
• lidé MeSH
• mužské pohlaví MeSH
• Publikační typ
• časopisecké články MeSH
• kazuistiky MeSH

We report a case of a metal splinter ejected by a circular saw tooth from a wooden board into the left ventricle of the heart. A 35-year old man was admitted second day after accident attributed to work complaining about general weakness. Only a small non-bleeding wound was found near his sternum. CT scan showed a metal wire entrapped inside his heart. Successful removal was done during surgery.

• Klíčová slova
• Foreign body, Intracardiac migration, Left ventricle, Metal splinter,
• MeSH
• cizí tělesa diagnóza   chirurgie   MeSH
• dospělí MeSH
• echokardiografie MeSH
• kardiochirurgické výkony metody   MeSH
• lidé MeSH
• penetrující rány diagnóza   chirurgie   MeSH
• počítačová rentgenová tomografie MeSH
• poranění srdce diagnóza   chirurgie   MeSH
• srdeční komory diagnostické zobrazování   zranění   chirurgie   MeSH
• Check Tag
• dospělí MeSH
• lidé MeSH
• mužské pohlaví MeSH
• Publikační typ
• časopisecké články MeSH
• kazuistiky MeSH

The measurement of cutting forces permits building of physic-mechanical cutting models for a better understanding of the phenomena observed during cutting. It also permits the design and optimization of processes, machines, tools, and wood preparation. Optimization of cutting conditions of wood-based materials can decrease the cutting forces, which directly relates to the energy consumption and surface quality. The sawdust analysis may serve for analysis of cutting kinematics and occupational health risk. The aim of the study was to estimate the correlation between the feed rate and both feed force and sawdust particle size produced during particleboard circular sawing. A saw machine type K700 was used in experiments. There were three feed rates of 12, 18, and 24 m/min executed by a horizontal pneumatic actuator fixed to the sliding side table of the saw machine. Based on the results of the experiments, a positive correlation was observed between the feed rate in a circular sawing process and feed forces and an unexpected particle size distribution depending on the feed rate.

• Klíčová slova
• circular saw, feed force, particleboard, sawdust particle size distribution,
• Publikační typ
• časopisecké články MeSH

• MeSH
• lidé MeSH
• mladiství MeSH
• penetrující rány chirurgie   MeSH
• poranění hrudníku chirurgie   MeSH
• poškození plic MeSH
• pracovní nehody * MeSH
• Check Tag
• lidé MeSH
• mladiství MeSH
• mužské pohlaví MeSH
• Publikační typ
• anglický abstrakt MeSH
• časopisecké články MeSH
• kazuistiky MeSH

Penetrating heart injuries are immediate life-threatening situations. We present a case report of a 44-year-old man with a foreign body in his right heart. The injury happened while the man was working with a circular saw 15 months prior to the actual diagnosis. With respect to the size of the foreign body, its close proximity to the right coronary artery, the potential risk of bleeding, embolization, endocarditis or pericarditis, surgical therapy was indicated in spite of the fact that the patient was asymptomatic. The foreign body (a spring-segment of a roller blind) was successfully removed.

• MeSH
• cizí tělesa diagnóza   etiologie   chirurgie   MeSH
• dospělí MeSH
• echokardiografie MeSH
• granulom z cizího tělesa diagnóza   etiologie   chirurgie   MeSH
• koronární angiografie MeSH
• koronární cévy zranění   chirurgie   MeSH
• kovy * MeSH
• lidé MeSH
• penetrující rány diagnóza   etiologie   chirurgie   MeSH
• pooperační komplikace chirurgie   MeSH
• poranění srdce diagnóza   etiologie   chirurgie   MeSH
• reoperace MeSH
• srdeční komory zranění   chirurgie   MeSH
• trikuspidální chlopeň zranění   chirurgie   MeSH
• vyvolaná zástava srdce MeSH
• Check Tag
• dospělí MeSH
• lidé MeSH
• mužské pohlaví MeSH
• Publikační typ
• časopisecké články MeSH
• kazuistiky MeSH
• Názvy látek
• kovy * MeSH

In their case report the authors deal with the loss tissue injury of the proximal phalanx of the thumb caused by a circular saw. The first treatment on the day of the injury was carried out at the local clinic, the edges of the wound were trimmed and the residual small bone fragments were removed. Then suture was made of the dorsal aponeurosis and a K-wire was drilled in percutaneously through the distal phalanx into the base of the proximal phalanx in order to maintain the distance between the fragments. Wide-spectrum antibiotics were applied together with antitetanus-toxic injections and anti-gangrenous serum. After 9 weeks when the wound was healed per primam the patient was sent for further treatment to the central clinic. There they introduced extension through the nail of the thumb and left it there for 15 days. 11 weeks after the injury the patients was operated on. A bone graft was made from part of 6th rib and fixed to the residue of the base by a T-shaped plate. The distal phalanx was then transfixed to the bone graft by 2 crossed-K-wires. The wound healed per primam, K-wires were removed after 6 weeks. The grasping function of the hand was preserved, the residual motion was possible in the metacarpophalangeal joint of the thumb, interphalangeal arthrodesis was stable. The patient resumed his original job as a painter.

• MeSH
• dospělí MeSH
• kosti a kostní tkáň zranění   chirurgie   MeSH
• lidé MeSH
• metody MeSH
• palec ruky zranění   chirurgie   MeSH
• pracovní nehody MeSH
• transplantace kostí * MeSH
• žebra MeSH
• Check Tag
• dospělí MeSH
• lidé MeSH
• mužské pohlaví MeSH
• Publikační typ
• anglický abstrakt MeSH
• časopisecké články MeSH
• kazuistiky MeSH

Electron microscopy (EM) is a key tool for studying the microstructure of wood; however, observing uncoated samples poses a challenge due to surface charging. This study aims to identify the critical voltage that allows for the effective observation of uncoated wood samples without significant loading. As part of the experiment, samples of different wood species were tested, including Acacia (Robinia pseudoacacia L.), Oak (Quercus robur L.), Maple (Acer pseudoplatanus spp.), Ash (Fraxinus excelsior L.), Spruce (Picea abies (L.) Karst.), Thermowood (Thermal modifed Spruce), Garapa (Apuleia leiocarpa), Ipé (Handroanthus spp.), Merbau (Intsia bijuga), and Massaranduba (Manilkara spp.). Several methods were tested for surface preparation for SEM analysis, including the use of a circular saw, a hand milling machine, and a microtome. The results show that the optimal voltage for observing uncoated wood samples varied depending on the wood species. Regarding the selection of wood species and the results obtained, it was found that uncoated samples could be effectively observed. This finding suggests that practical observations can be accelerated and more cost-effective, as all wood species exhibited the required voltage range of 1 kV to 1.6 kV. Additionally, it was determined that using a secondary electron detector was optimal for such observations, as it provided a sufficiently strong signal even at relatively low voltages. Conversely, when using a backscattered electron detector, it was more beneficial to use coated samples to achieve a sufficient signal at higher voltages. This study brings new knowledge that will facilitate further research and applications of electron microscopy in the study of other wood species or wood-based materials.

• Klíčová slova
• SEM analysis, density, electron microscopy (EM), surface, voltage, wood,
• Publikační typ
• časopisecké články MeSH

This computational study investigates the effect of shape (defect contour curvature) and bone-implant interface (osteotomy angle) on the stress distribution within PMMA skull implants. Using finite element methodology, 15 configurations--combinations of simplified synthetic geometric shapes (circular, square, triangular, irregular) and interface angulations--were simulated under 50N static loads. Furthermore, the implant fixation devices were modelled and analysed in detail. Negative osteotomy configurations demonstrated the largest stresses in the implant (275 MPa), fixation devices (1258 MPa) and bone strains (0.04). The circular implant with zero and positive osteotomy performed well with maximum observed magnitudes of--implant stress (1.2 MPa and 1.2 MPa), fixation device stress (11.2 MPa and 2.2 MPa), bone strain (0.218e-3 and 0.750e-4). The results suggest that the preparation of defect sites is a critical procedure. Of the greatest importance is the angle at which the edges of the defect are sawed. If under an external load, the implant has no support from the interface and the stresses are transferred to the fixation devices. This can endanger their material integrity and lead to unphysiological strains in the adjacent bone, potentially compromising the bone morphology required for anchoring. These factors can ultimately weaken the stability of the entire implant assembly.

• Klíčová slova
• 3D printing, Cranial trauma, Osteotomy, Patient-specific modelling, Rehabilitation,
• MeSH
• analýza metodou konečných prvků MeSH
• analýza zatížení zubů MeSH
• lebka * MeSH
• lidé MeSH
• mechanický stres MeSH
• polymethylmethakrylát MeSH
• protézy a implantáty * MeSH
• rozhraní kost/implantát * MeSH
• zubní implantáty * MeSH
• Check Tag
• lidé MeSH
• Publikační typ
• časopisecké články MeSH
• práce podpořená grantem MeSH
• Názvy látek
• polymethylmethakrylát MeSH
• zubní implantáty * MeSH