Depressed skull fractures occur when broken bones displace inward, meaning that a portion of the outer table of the fracture line lies below the normal anatomical position of the inner table. They typically result from force trauma, when the skull is struck by an object with a moderately large amount of kinetic energy but a small surface area, or when an object with a large amount of kinetic energy impacts only a small area of the skull. In the present case, a depressed fracture of the frontal bone was detected at the autopsy of a 52-year-old man who, according to the belated confession of the assailant, was kicked in the head. The assailant was wearing sneakers. Could such a fracture be caused \"just\" by a kick? In this case it was possible due to an extraordinarily thin cranial vault (0.2 cm frontal, 0.3 cm occipital), which allowed the fractures to occur from a kinetic force that might not have been sufficient with a normal cranial vault thickness. An important role in the forensic analysis of the case was played by the 3D CT reconstruction.

Kicking strikes are fundamental in combat sports such as Taekwondo, karate, kickboxing, Muay Thai, and mixed martial arts. This review aimed to explore the measurement methods, kinematics such as velocities, kinetics such as impact force, determinants, and injury potential of kicking strikes in combat sports. Searches of Academic Search Premier, The Allied and Complementary Medicine Database, CINAHL Plus, MEDLINE, SPORTDiscus, Scopus, and Web of Science databases were conducted for studies that measured kicking velocity and impact force. A total of 88 studies were included in the review. Studies most frequently involved only male participants (49%) aged between 18 and 30 years of age (68%). Studies measuring velocity predominantly implemented camera-based motion capture systems (96%), whereas studies measuring impact force displayed considerable heterogeneity in their measurement methods. Five primary strikes were identified for which foot velocities ranged from 5.2 to 18.3 m/s and mean impact force ranged from 122.6 to 9015 N. Among the techniques analysed, the roundhouse kick exhibited the highest kicking velocity at 18.3 m/s, whilst the side kick produced the highest impact force at 9015 N. Diverse investigation methodologies contributed to a wide value range for kicking velocities and impact forces being reported, making direct comparisons difficult. Kicking strikes can be categorised into throw-style or push-style kicks, which modulate impact through different mechanisms. Kicking velocity and impact force are determined by several factors, including technical proficiency, lower body strength and flexibility, effective mass, and target factors. The impact force generated by kicking strikes is sufficient to cause injury, including fracture. Protective equipment can partially attenuate these forces, although more research is required in this area. Athletes and coaches are advised to carefully consider the properties and potential limitations of measurement devices used to assess impact force.

BACKGROUND: The number of users of electric scooters, which provide swift and convenient mobility options, has increased sharply over recent years as their distribution as a shared service has expanded. Although the number of accidents and related damage has increased accordingly, limited research has analyzed data on the new types of accidents arising from electric scooters. This study aimed to analyze data on trauma characteristics due to accidents that occurred during electric scooter use.
METHODS: A retrospective chart review was conducted for patients who visited the regional trauma center of our institute due to electric scooter accidents from April 2018 to October 2021. Information was extracted on helmet-wearing status, sex, age, drinking status, accident timeframe, accident mechanism, electric scooter proficiency (period of use), injury severity, severe trauma, lethality, admission to the intensive care unit, surgery under general anesthesia, and the trauma region.
RESULTS: Among the 108 patients involved in electric scooter accidents, 92 patients were not wearing a helmet. Eighty-nine patients (85.2%) were male. The average age of the patients without a helmet was 31.3 years, while that of patients with a helmet was 34.1 years. The most frequent causes of accidents were lack of electric scooter operation experience and falling off the scooter due to obstacles (90 cases). Whether surgery was performed under general anesthesia was not associated with helmet use or non-use, although all patients who underwent facial fracture surgery were not wearing a helmet.
CONCLUSIONS: The craniofacial region was most frequently affected in electric scooter accidents and wearing a helmet was the best way to prevent craniofacial trauma. Although helmet-wearing is mandatory, the majority of treated patients were not wearing a helmet at the time of injury. Thus, there is an urgent need to introduce a helmet rental system, as well as strict legal requirements, to improve this situation.

BACKGROUND: To handle the competition demands, sparring drills are used for specific technical-tactical training as well as physical-physiological conditioning in combat sports. While the effects of different area sizes and number of within-round sparring partners on physiological and perceptive responses in combats sports were examined in previous studies, technical and tactical aspects were not investigated. This study investigated the effect of different within-round sparring partners number (i.e., at a time; 1 vs. 1, 1 vs. 2, and 1 vs. 4) and area sizes (2 m × 2 m, 4 m × 4 m, and 6 m × 6 m) variation on the technical-tactical aspects of small combat games in kickboxing.
METHODS: Twenty male kickboxers (mean ± standard deviation, age: 20.3 ± 0.9 years), regularly competing in regional and national events randomly performed nine different kickboxing combats, lasting 2 min each. All combats were video recorded and analyzed using the software Dartfish.
RESULTS: Results showed that the total number of punches was significantly higher in 1 versus 4 compared with 1 versus 1 (p = 0.011, d = 0.83). Further, the total number of kicks was significantly higher in 1 versus 4 compared with 1 versus 1 and 1 versus 2 (p < 0.001; d = 0.99 and d = 0.83, respectively). Moreover, the total number of kick combinations was significantly higher in 1 versus 4 compared with 1 versus 1 and 1 versus 2 (p < 0.001; d = 1.05 and d = 0.95, respectively). The same outcome was significantly lower in 2 m × 2 m compared with 4 m × 4 m and 6 m × 6 m areas (p = 0.010 and d = - 0.45; p < 0.001 and d = - 0.6, respectively). The number of block-and-parry was significantly higher in 1 versus 4 compared with 1 versus 1 (p < 0.001, d = 1.45) and 1 versus 2 (p = 0.046, d = 0.61) and in 2 m × 2 m compared with 4 m × 4 m and 6 × 6 m areas (p < 0.001; d = 0.47 and d = 0.66, respectively). Backwards lean actions occurred more often in 2 m × 2 m compared with 4 m × 4 m (p = 0.009, d = 0.53) and 6 m × 6 m (p = 0.003, d = 0.60). However, the number of foot defenses was significantly lower in 2 m × 2 m compared with 6 m × 6 m (p < 0.001, d = 1.04) and 4 m × 4 m (p = 0.004, d = 0.63). Additionally, the number of clinches was significantly higher in 1 versus 1 compared with 1 versus 2 (p = 0.002, d = 0.7) and 1 versus 4 (p = 0.034, d = 0.45).
CONCLUSIONS: This study provides practical insights into how to manipulate within-round sparring partners\' number and/or area size to train specific kickboxing technical-tactical fundamentals.
BACKGROUND: This study does not report results related to health care interventions using human participants and therefore it was not prospectively registered.

OBJECTIVE: While kicking in Rugby Union can be influential to match outcome, the epidemiology of kicking injuries remains unknown. This study therefore aimed to investigate the epidemiology of injuries attributed to kicking in professional rugby, including playing position-specific effects and differences in kicking volumes and kick types.
METHODS: Fifteen seasons of injury surveillance data and two seasons of match kicking characteristics from professional rugby players were analyzed. Incidence, propensity, and severity of kicking-related injuries were calculated together with the locations and types of these injuries. Position-related differences in match kicking types and volumes were also established.
RESULTS: Seventy-seven match and 55 training acute-onset kicking injuries were identified. The match kicking injury incidence for backs was 1.4/1000 player-match-hours. Across all playing positions, the propensity for match kicking injury was 0.57 injuries/1000 kicks. Fly-halves sustained the greatest proportion of match kicking injuries (47%) and performed the greatest proportion of match kicks (46%); an average propensity for match kicking injury (0.58/1000 kicks). Scrum-halves executed 27% of match-related kicks but had a very low propensity for match kicking injury (0.17/1000 kicks). All other positional groups executed a small proportion of match-related kicks but a high propensity for match kicking injury. Ninety-two percent of match kicking injuries occurred in the pelvis or lower limb, with the majority sustained by the kicking limb. 21% of all match kicking injuries were associated with the rectus femoris muscle.
CONCLUSIONS: Match kicking profiles and kicking injuries sustained are position-dependent, which provides valuable insight for developing player-specific conditioning and rehabilitation protocols.

We aimed to identify differences in kicking leg and torso mechanics between groups of rugby place kickers who achieve different performance outcomes, and to understand why these features are associated with varying levels of success. Thirty-three experienced place kickers performed maximum effort place kicks, whilst three-dimensional kinematic (240 Hz) and ground reaction force (960 Hz) data were recorded. Kicking leg and torso mechanics were compared between the more successful (\'long\') kickers and two sub groups of less successful kickers (\'short\' and \'wide-left\') using magnitude-based inferences and statistical parametric mapping. Short kickers achieved substantially slower ball velocities compared with the long kickers (20.8 ± 2.2 m/s vs. 27.6 ± 1.7 m/s, respectively) due to performing substantially less positive hip flexor (normalised mean values = 0.071 vs. 0.092) and knee extensor (0.004 vs. 0.009) joint work throughout the downswing, which may be associated with their more front-on body orientation, and potentially a lack of strength or intent. Wide-left kickers achieved comparable ball velocities (26.9 ± 1.6 m/s) to the long kickers, but they were less accurate due to substantially more longitudinal ball spin and a misdirected linear ball velocity. Wide-left kickers created a tension arc across the torso and therefore greater positive hip flexor joint work (normalised mean = 0.112) throughout the downswing than the long kickers. Whilst this may have assisted kicking foot velocity, it also induced greater longitudinal torso rotation during the downswing, and may have affected the ability of the hip to control the direction of the foot trajectory.

In many sports, athletes perform motor tasks that simultaneously require both speed and accuracy for success, such as kicking a ball. Because of the biomechanical trade-off between speed and accuracy, athletes must balance these competing demands. Modelling the optimal compromise between speed and accuracy requires one to quantifyhow task speed affects the dispersion around a target, a level of experimental detail not previously addressed. Using soccer penalties as a system, we measured two-dimensional kicking error over a range of speeds, target heights, and kicking techniques. Twenty experienced soccer players executed a total of 8466 kicks at two targets (high and low). Players kicked with the side of their foot or the instep at ball speeds ranging from 40% to 100% of their maximum. The inaccuracy of kicks was measured in horizontal and vertical dimensions. For both horizontal and vertical inaccuracy, variance increased as a power function of speed, whose parameter values depended on the combination of kicking technique and target height. Kicking precision was greater when aiming at a low target compared to a high target. Side-foot kicks were more accurate than instep kicks. The centre of the dispersion of shots shifted as a function of speed. An analysis of the covariance between horizontal and vertical error revealed right-footed kickers tended to miss below and to the left of the target or above and to the right, while left-footed kickers tended along the reflected axis. Our analysis provides relationships needed to model the optimal strategy for penalty kickers.

BACKGROUND: The incidence of fractures after a kick, coupled with marked soft tissue trauma at the site of injury, suggests that the force of a kick from the hind limb of a horse is enormous. The goal of this study was to measure this force and to investigate whether the Tekscan F-SCAN in-shoe pressure measuring system is suitable for quantification of the impact strength of a kick from a horse. The system was tested in 6 horses that had undergone clinical examination and gait analysis. The sensor-shoe combination was attached to each hind foot and the horse was stimulated to kick against a wall. The F-SCAN system measured the maximum vertical and horizontal force (N), the main contact area (cm2) of the sole with the floor (stance phase limb) or wall (kicking limb) and the duration (sec) that the sole was in contact with the floor or wall. In addition, each kicking event was recorded with a video camera for subjective evaluation. The mean kicking force measured was lower than that recorded in horses trotting on a treadmill, where the forces exerted on one limb were similar to the horse\'s body weight. The results of this study indicate that the Tekscan F-SCAN system is not ideally suited to measure the force of a kick of a horse in vivo.
Die Häufigkeit von Frakturen und die ausgedehnten Weichteiltraumata nach Schlagverletzungen lassen vermuten, dass die bei einem Hufschlag übertragene Kraft sehr hoch sein muss. Ziel dieser Arbeit war es, diese Kraft zu messen und zu untersuchen, ob sich das Tekscan F-Scan System dazu eignet, die Schlagkraft des Pferdes zu quantifizieren. Nach vorangegangener klinischer und orthopädischer Untersuchung wurde das System an 6 Pferden getestet, indem der dazugehörige Sensor in einen Hufschuh eingebettet und das Pferd anschliessend zum Ausschlagen gegen eine Wand stimuliert wurde. Das F-Scan System berechnete bei jedem Schlag die maximale vertikale bzw. horizontale Kraft (N), die Kontaktfläche (cm2) der Hufsohle mit dem Boden (Standbein) oder der Wand (schlagendes Bein), sowie die Kontaktdauer (sec) mit dem Boden oder der Wand. Gleichzeitig wurde jedes Ausschlagen auf Video aufgezeichnet und die Schlagkraft auch subjektiv bewertet. Die gemessenen Kräfte waren jedoch tiefer als die in einer vorangegangenen Studie, bei der Messungen an auf dem Laufband trabenden Pferden durchgeführt wurden. Dabei entsprachen die auf die Gliedmassen einwirkenden Kräfte etwa dem Gewicht des Pferdes. Die Resultate unserer Studie weisen darauf hin, dass das Tekscan F-Scan System nicht ideal zur Messung der Schlagkraft eines Pferdes in vivo ist.
La fréquence des fractures et les importants dégâts aux tissus mous consécutifs à des coups de pieds laissent à penser que la force de frappe transmise à cette occasion doit être très importante. Le but du présent travail était de mesurer cette force et de voir si le système F-Scan Tekscan est adapté pour quantifier la force de frappe d’un cheval. Après un examen clinique et orthopédique, le système a été utilisé sur 6 chevaux, en incluant le senseur dans une hipposandale et en stimulant ensuite le cheval pour qu’il rue contre une paroi. Le système F-Scan a mesuré lors de chaque coup de pied la force maximale verticale respectivement horizontale (N), la surface de contact (cm2) de la sole avec le sol (membre à l’appui) ou avec la paroi (membre donnant le coup) ainsi que la durée de contact avec le sol respectivement avec la paroi. Chaque coup de pied a simultanément été enregistré sur vidéo et le force du coup a été estimée subjectivement. Les forces mesurées étaient toutefois plus faibles que celles enregistrées chez des chevaux au trot sur un tapis roulant dans une étude précédente. Les forces exercées sur les membres étaient globalement égales au poids du cheval. Les résultats de notre étude laissent à penser que le système F-Scan Tekscan n’est pas idéal pour mesurer la force de frappe d’un cheval.
L’incidenza delle fratture e degli estesi traumi dei tessuti molli dovuti a lesioni da impatto fanno sospettare che la forza trasferita dallo scalpitio dello zoccolo debba essere molto elevata. Lo scopo di questo studio era quello di misurare questa forza e di indagare se il sistema F-Scan di Tekscan fosse idoneo a quantificare la potenza di impulso del cavallo. Dopo un esame clinico e ortopedico eseguito in precedenza, il sistema è stato testato su 6 cavalli nei quali è stato incorporato il relativo sensore nella scarpa e sono stati stimolati a scalpitare contro una parete. Il sistema F-Scan ha calcolato ad ogni colpo, la forza verticale e orizzontale massima (N), la zona di contatto (cm2) dello zoccolo con il suolo (arto posteriore) o la parete (arto scalpitante), e il tempo di contatto (secondi) contro il suolo o la parete. Allo stesso tempo, lo scalpitio è stato videoregistrato ed è stata valutata soggettivamente la potenza impiegata. Le forze misurate, tuttavia, erano inferiori a quelle di uno studio precedente le cui misure erano state raccolte su un tapis roulant per cavalli. Le forze che agiscono sugli arti sono approssimativamente equivalenti al peso del cavallo. I risultati del nostro studio indicano che il sistema F-Scan di Tekscan non è idoneo a misurare la potenza d’impulso di un cavallo.

We present the case of a 38-year-old woman admitted to our outpatient clinic with accelerating back pain and fatigue following a kick to her back by her husband. Upon arrival, we detected ST segment elevation in the D1, aVL, and V2 leads and accelerated idioventricular rhythm. She had pallor and hypotension consistent with cardiogenic shock. We immediately performed coronary angiography and found a long dissection starting from the mid-left main coronary artery and progressing into the mid-left anterior descending (LAD) and circumflex arteries. She was then transferred to the operating room for surgery. A saphenous vein was grafted to the distal LAD. Since the patient was hypotensive under noradrenaline and dopamine infusions, she was transferred to the cardiovascular surgery intensive care unit on an extracorporeal membrane oxygenator and intra-aortic balloon pump. During follow-up, her blood pressure remained low, at approximately 60/40 mmHg, despite aggressive inotropic and mechanical support. On the second postoperative day, asystole and cardiovascular arrest quickly developed, and despite aggressive cardiopulmonary resuscitation, she died.

The aim of this study was to analyse the characteristics of the asymmetries in the dominant and non-dominant limbs when kicking stationary and rolling balls. Ten experienced Brazilian amateur futsal players participated in this study. Each participant performed kicks under two conditions (stationary ball vs. rolling ball) with the dominant and non-dominant limbs (five kicks per condition per limb). We analysed the kicking accuracy, ball and foot velocities, angular joint displacement and velocity. The asymmetry between the dominant and non-dominant limbs was analysed by symmetry index and two-way repeated measures ANOVA. The results did not reveal any interaction between the condition and limb for ball velocity, foot velocity and accuracy. However, kicking with the dominant limb in both kicks showed higher ball velocity (stationary ball: dominant - 24.27 ± 2.21 m · s(-1) and non-dominant - 21.62 ± 2.26 m · s(-1); rolling ball: dominant - 23.88 ± 2.71 m · s(-1) and non-dominant - 21.42 ± 2.25 m · s(-1)), foot velocity (stationary ball: dominant - 17.61 ± 1.87 m · s(-1) and non-dominant - 15.58 ± 2.69 m · s(-1); rolling ball: dominant - 17.25 ± 2.26 m · s(-1) and non-dominant - 14.77 ± 2.35 m · s(-1)) and accuracy (stationary ball: dominant - 1.17 ± 0.84 m and non-dominant - 1.56 ± 1.30 m; rolling ball: dominant - 1.31 ± 0.91 m and non-dominant - 1.97 ± 1.44 m). In addition, the angular joint adjustments were dependent on the limb in both kicks (the kicks with non-dominant limb showed lower hip external rotation than the kicks with the dominant limb), indicating that the hip joint is important in kick performance. In conclusion, the kicks with the non-dominant limb showed different angular adjustments in comparison to kicks with the dominant limb. In addition, kicking a rolling ball with the non-dominant limb showed higher asymmetry for accuracy, indicating that complex kicks are more asymmetric.