ABSTRACT
BACKGROUND: Kendo, a martial art developed by the samurai, is rooted deep in Japanese culture with traditional armor that has seen little change over the past centuries. Despite its century-old design, kendo helmets are manufactured without third-party testing to verify their quality and effectiveness against head trauma. OBJECTIVE: To evaluate the effectiveness of different helmet stitching patterns and padding materials in mitigating impact forces that could lead to sports-related concussions (SRC) in kendo, and to assess variations in safety performance across different genders and kendo ranks (Dan and Kyu). METHODS: We collected data from 10 kendo practitioners (six males and four females), analyzing over 4,000 strikes using shinai on a sensor-equipped mannequin. Various helmet stitching patterns (ranging from 2 mm to 9 mm) and padding types (polyurethane-based and different thicknesses of cotton-based pads) were tested under controlled conditions simulating realistic impacts encountered in kendo practice. RESULTS: The results indicated that helmets with wider stitching patterns (e.g. 8 mm and 9 mm) generally offered better energy absorption, exhibiting statistically significant lower mean g-forces with a 95% confidence interval compared to tighter patterns (2 mm, 4 mm, 6 mm, and 8 mm x 2 mm) (p < 0.001). Additionally, the polyurethane-based padding outperformed cotton-based padding by a statistically significant reduction of impact force (p < 0.001). Significant differences in striking force were also observed between genders and ranks, with male and higher-rank (Dan) practitioners delivering stronger impacts (both p < 0.001). CONCLUSIONS: This study highlights the critical influence of helmet stitching patterns and padding materials on the protective capabilities against concussions in kendo. Even though helmets with narrower stitching patterns cost more, helmets with wider stitching patterns and polyurethane padding material provide enhanced safety benefits. We do not know how the difference in striking force between genders and ranks affects the outcome of a kendo match.
ABSTRACT
The primary insult in vertebral artery dissections (VADs) involves a tear in the vertebral artery intima, resulting in potential thrombus formation and an elevated risk of cerebrovascular events, such as stroke. Despite its relatively low overall incidence rate, VADs contribute to a significant proportion of ischemic strokes within the younger population. VAD has been associated with various risk factors including but not limited to neck trauma from chiropractic manipulation and significant neck movements. Our patient initially presented with a worsening occipital headache but was discharged due to the absence of any red-flag symptoms. However, the patient shortly returned to the ED upon worsening symptoms, and despite the lack of apparent neurological deficits, the patient's history of cervical spine manipulation and exposure to neck trauma risk activities (roller coaster riding) increased suspicion for VAD. This case highlights the importance of considering VAD as a differential diagnosis in young patients presenting with unexplained headaches and neck pain following events that exert stress on the vertebral arteries, such as roller coaster rides and chiropractic neck manipulation. When managed properly, the long-term prognosis of VAD is generally favorable; however, the risk of recurrent dissection and stroke still remains. Thus, this case further emphasizes the need for timely intervention and the role of dual anti-platelet therapy (DAPT) in the management of VAD to prevent further complications such as stroke.
ABSTRACT
Annually, millions of people worldwide are exposed to Campylobacter, a species of bacteria that commonly causes gastroenteritis and in cases of immunocompromised individuals, can also lead to life-threatening complications. After stool cultures are obtained, the usual treatment for infectious diarrhea involves metronidazole and quinolones such as ciprofloxacin or levofloxacin. Quinolones are a family of broad-spectrum antibiotics known to be effective against various gram-negative infections that also include Campylobacter jejuni (C. jejuni). However, due to adverse side effects and bacterial resistance risks that may exist with medication use, they are no longer used as a first line. Our patient, initially treated with ceftriaxone for symptoms resembling bacterial meningitis, pneumonia, and infectious diarrhea, showed minimal to no improvement. Subsequent cerebral spinal fluid (CSF) ruled out meningitis while stool studies confirmed C. jejuni as the causative agent. A switch to levofloxacin resulted in a noticeable improvement in the patient's condition. This case emphasizes the importance of considering changes in antibiotic regimen from ceftriaxone to quinolones when faced with persistent infectious diarrhea, due to the high prevalence of ceftriaxone resistance in C. jejuni infections.
