Examination for the Factors Involving to Joint Effusion in Patients with Temporomandibular Disorders Using Magnetic Resonance Imaging.

BACKGROUND: This study investigated the factors involving joint effusion in patients with temporomandibular disorders. METHODS: The magnetic resonance images of 131 temporomandibular joints (TMJs) of patients with temporomandibular disorders were evaluated. Gender, age, disease classification, duration of manifestation, muscle pain, TMJ pain, jaw opening disturbance, disc displacement with and without reduction, deformation of the articular disc, deformation of bone, and joint effusion were investigated. Differences in the appearance of symptoms and observations were evaluated using cross-tabulation. The differences in the amounts of synovial fluid in joint effusion vs. duration of manifestation were analyzed using the Kruskal-Wallis test. Multiple logistic regression analysis was performed to analyze the factors contributing to joint effusion. RESULTS: Manifestation duration was significantly longer when joint effusion was not recognized (p < 0.05). Arthralgia and deformation of the articular disc were related to a high risk of joint effusion (p < 0.05). CONCLUSIONS: The results of this study suggest that joint effusion recognized in magnetic resonance imaging was easily observed when the manifestation duration was short, and arthralgia and deformation of the articular disc were related to a higher risk of joint effusion.

Difference in thickness of vacuum-formed mouthguards using ethylene vinyl acetate and polyolefin sheets.

BACKGROUND/AIM: Polyolefin sheets are fabricated in the same manner as ethylene vinyl acetate sheets. The aim of this study was to examine the difference of vacuum-formed mouthguard thickness according to each heating condition using ethylene vinyl acetate and polyolefin sheets. MATERIALS AND METHODS: Mouthguard sheets of 3.0 mm ethylene vinyl acetate and polyolefin were vacuum-formed on working models at three heating temperatures: 85, 95, and 105°C. The thickness of the mouthguard was measured at the labial surface of the central incisor, the buccal surface of the first molar, and occlusal surface of the first molar. Differences in the thickness of the mouthguards according to the sheet materials and the heating conditions were analyzed by two-way analysis of variance. RESULTS: Mouthguard thickness varied between the ethylene vinyl acetate and the polyolefin sheets (p < .01), and the thickness of the ethylene vinyl acetate sheet was greater than that of the polyolefin sheet at all heating conditions. The thicknesses of mouthguards fabricated using the ethylene vinyl acetate and the polyolefin sheets were not different for the three heating conditions in this study. CONCLUSIONS: The thickness was greater for mouthguards fabricated using ethylene vinyl acetate sheet than when polyolefin sheet was used. The thickness of the mouthguards was not different for the three heating temperatures for both the ethylene vinyl acetate and the polyolefin sheets.

Medical care provision at the venue of the weightlifting event of the Tokyo 2020 Olympic Games.

Purpose: This study aimed to investigate the medical care provided at the venue of the weightlifting event of the Tokyo 2020 Olympic Games. Methods: We retrospectively evaluated athletes who availed of medical services at the venue during the weightlifting event of the Tokyo 2020 Olympic Games. In total, 194 athletes participated in the weightlifting competition.Injuries and illnesses were classified into cases handled without physician or cases requiring medical examination by a physician. These were tabulated for each examination location (athlete medical station, field of play [FOP], first-aid station of training floor or warm-up area). Results: Throughout the event, a cumulative total of 132 people used the venue medical services. Nine athletes required medical attention at the athlete medical stations. Of these nine cases, six occurred on the training floor. In the FOP, nine athletes were examined. Two experienced light-headedness, two had knee pain, and the rest had other symptoms. No athletes wanted to undergo medical examination at the athlete medical station. 89 medical procedures were performed in the first-aid station on the training floor, including 52 tapings and 37 ice compressions, and the most frequent body part which needed treatment was the knee, followed by the fingers. At the first-aid station on the match floor, 25 medical procedures were performed, including 17 ice compressions, 5 haemostasis, and 4 tapings. The body parts that most frequently needed treatment were the fingers, knees, and lower legs. Conclusion: Several athletes needed treatment; however, only a few required medical care from a physician.

Throwing Injuries in Youth Baseball Players: Can a Prevention Program Help? A Randomized Controlled Trial.

BACKGROUND: Throwing injuries of the shoulder and elbow are common among youth baseball players. HYPOTHESIS: A prevention program will reduce the incidence of throwing injuries of the shoulder and elbow by 50% among youth baseball players. STUDY DESIGN: Randomized controlled trial; Level of evidence, 1. METHODS: The authors block randomized 16 youth baseball teams consisting of 237 players aged 9 to 11 years into an intervention group (8 teams, 117 players) and a control group (8 teams, 120 players). The intervention program consisted of 5 stretching, 2 dynamic mobility, and 2 balance training exercises performed during warm-up. Both groups were followed up for 12 months, during which the incidence of shoulder and elbow injuries was recorded. In addition, ball speed during pitching as a performance-related factor and variables of physical function (passive range of motion of the elbow, shoulder and hip, dynamic balance, and thoracic kyphosis angle) were assessed during the pre- and postintervention periods. RESULTS: The incidence of shoulder and elbow injuries in the intervention group (1.7 per 1000 athlete-exposures) was significantly lower than that in the control group (3.1 per 1000 athlete-exposures) (hazard ratio, 1.940; 95% CI, 1.175-3.205; P = .010). The factors related to pitching performance, as assessed by ball speed, tended to increase in the intervention group as compared with the control group (P = .010). The program also improved shoulder horizontal adduction deficits on the dominant side, hip internal rotation on the nondominant side, and the thoracic kyphosis angle. CONCLUSION: A prevention program decreases throwing injuries of the shoulder and elbow and enhances the parameter of pitching performance in youth baseball players.

Efficacy of a Prevention Program for Medial Elbow Injuries in Youth Baseball Players.

BACKGROUND: Youth baseball players are at high risk for elbow injuries, which can lead to future functional disability. PURPOSE: To evaluate the effectiveness of a prevention program to lower the risk of medial elbow injury in these athletes. STUDY DESIGN: Cohort study; Level of evidence, 2. METHODS: Youth baseball players, 8 to 11 years old, without a history of elbow and shoulder pain, were allocated to either the intervention (n = 136) or control (n = 169) group. The intervention consisted of 9 strengthening and 9 stretching exercises, performed during warm-up or at home, with high compliance defined as completion of the program 1 or more times per week. The following outcome variables were measured: clinical assessment of the elbow and shoulder joint, ultrasonography assessment of the elbow, and assessment of physical function (passive range of motion of the elbow, shoulder, and hip; strength of the shoulder and scapular muscles; and measurement of the thoracic kyphosis angle). The clinical and ultrasonography assessments were measured at baseline and at 3-month intervals over the 1-year follow-up. Physical function outcomes were measured at baseline and at the endpoint of the follow-up. The primary endpoint of effectiveness was the incidence of medial elbow injury. Secondary endpoints were absolute measures of physical function and change in these measures over the 1-year follow-up. RESULTS: The incidence rate of medial elbow injury was significantly lower in the intervention group (0.8/1000 athlete-exposures) than the control group (1.7/1000 athlete-exposures) (hazard ratio, 50.8%; 95% CI, 0.292-0.882; P = .016). The program improved total range of shoulder rotation (dominant side), hip internal rotation (nondominant side), shoulder internal rotation deficit (bilaterally), lower trapezius muscle strength (dominant side), and the thoracic kyphosis angle. Improvements in the following variables of physical function were predictive of a lower rate of medial elbow injury: increased total shoulder total rotation (odds ratio [OR], 0.973; 95% CI, 0.950-0.997), increased hip internal rotation of the nondominant side (OR, 0.962; 95% CI, 0.936-0.989), and decreased thoracic kyphosis angle (OR, 1.058; 95% CI, 1.015-1.103). CONCLUSION: A prevention program aiming to improve physical function can prevent medial elbow injury in youth baseball players.

[Case of primary leiomyosarcoma of the seminal vesicle].

A 72-year-old male visited our hospital with a complaint of perineal and voiding pain. An elastic hard mass was palpated by rectal examination in the cranial lesion of prostate. On CT scan and MRI it was located at the site of the right seminal vesicle. Trans-rectal needle biopsy specimen showed leiomyosarcoma. Radical cystoprostatectomy with pelvic lymph node dissection was performed at Hokkaido University Hospital. Microscopic examination of the resected specimen revealed the tumor arose from the right seminal vesicle without involvement of the bladder and the prostate gland. Three months after the operation the tumor recurred at lung and pelvic lymph node. He died 10 month postoperatively. Autopsy finding showed many visceral organs metastases without local recurrence. In the past, nine cases of leiomyosarcoma of seminal vesicle were published in the literature. Including our case, pathological diagnosis by core needle biopsy was attempted in five cases, though accurate diagnosis was made in only two cases. In our case, Immunohistological study by SMA and desmin was useful for histological diagnosis preoperatively.