Objective：This study aimed to examine the relationship between the combined rotational range of motion of the thoracic spine and scapulothoracic joint and the maximum elbow valgus torque during pitching in male high school baseball players.

Method：The participants included 17 male high school baseball players who belonged to high-ranking schools in the prefectural tournament and had experience as pitchers. The combined range of motion of the thoracic spine rotation and the scapulothoracic joint was measured by the Lumber Locked Rotation test (LLR-t). The maximum elbow valgus torque during pitching was measured by PULSE Throw. The correlation between the angle of the LLR-t to the throwing and non-throwing sides and the elbow valgus torque was subsequently examined.

Result：A moderately significant negative correlation (r＝－0.49, p＝0.04) was observed between the LLR-t to the throwing side and maximum elbow valgus torque.

Conclusion：Evaluating the combined range of motion of the thoracic spine and the scapulothoracic joint, rather than the rotation of the thoracic spine alone, is beneficial for baseball elbow cases and injury prevention in high school baseball players.

Objective: The purpose of this study was to explore impacts of menstruation-related symptoms on athletic performance and response to menstruation-related problems (such as rate of gynecological consultations and consultation at sports sites) among female athletes belonging to school and community sports clubs. Our hypothesis was that although menstruation-related symptoms affect athletic performance, only a small number of athletes take action to combat these issues, for example by consulting with gynecologists.

Methods: This observational, cross-sectional study was based on a survey conducted from May 17 to 31, 2021 using Google Forms (Alphabet, Mountain View, CA, USA). Study targets were young female athletes aged 18-30 years who belonged to school sports clubs and local sports clubs. We asked about the presence or absence of condition fluctuations due to the menstrual cycle, influence of menstruation-related symptoms on sports activities, experience consulting a gynecologist, and consulting at sports sited, in addition to basic demographic information.

Results: The survey was distributed to 300 female athletes and 151 valid responses were received. In total, 121 (80.1 %) respondents stated that their condition fluctuates with their menstrual cycle, and influence of menstruation-related symptoms on sports activities was reported by 113 (74.8 %) respondents. There were 21 (13.9 %) respondents who had visited gynecologists, and 12 (7.9 %) respondents had discussed their menstrual problems with their coaches or other people at sports sites.

Conclusion: This study revealed that menstrual cycles and symptoms associated with menstruation affect the conditions of female athletes in sports club activities. This study contributes to existing research by considering the need for countermeasures against symptoms associated with menstruation at a wide range of athletic levels, and by highlighting issues relating to low rates of gynecological consultations and consultation in sports settings. We hope this study can be used as a basis to create an environment that facilitates healthy activities for female athletes.

Objective: The purpose of this study was to clarify the difference in knee extensor muscle strength in patients with medial patellofemoral ligament reconstruction (MPFLR) using artificial ligaments and MPFLR with concomitant tibial tubercle osteotomy (MPFLR+TTO).

Methods: Fifteen patients in the MPFLR group (follow-up time: 22.8±15.6 months) and 11 patients in the MPFLR+TTO group (follow-up time: 22.8±9.6 months) participated in the present study. The isometric knee extensor strength at 90° and 30° of knee flexion were measured for all participants. The differences and ratios in knee extensor strength between the operated and non-operated knees were determined.

Results: In the MPFLR group, there were no significant differences in isometric knee extensor strength between operated and non-operated knees. In the MPFLR+TTO group, the operated knee extensor strength was significantly lower than the non-operated knee. The isometric knee extensor strength ratio of the operated to the non-operated knee was significantly lower at 30° of knee flexion in the MPFLR+TTO group than in the MPFLR group.

Conclusion: Isolated MPFLR using artificial ligaments provided good recovery of knee extensor muscle strength. On the other hand, it was suggested that MPFLR with concomitant TTO remained the differences in knee extensor strength between operated and non-operated knees and postoperative recovery of knee extensor muscle strength was smaller than isolated MPFLR.

Objective: This study aimed to examine the relationship between foot arch height (FAH) measurement methods and the effects of foot arch morphology on the weight-bearing dorsiflexion range of motion (ROM) and balance function of the ankle.

Methods: In the study, 44 healthy adult students were included. The foot morphology was evaluated using four different FAH measurement methods, and the correlation between each measurement method was examined. The weight-bearing dorsiflexion ROM and static and dynamic balance ability were compared between the normal foot and low foot groups, which were classified according to the foot posture index-6.

Results: A certain degree of correlation was observed between each FAH measurement methods. However, there were no significant differences in the weight-bearing dorsiflexion ROM and static and dynamic balance ability between the normal foot and low foot groups.

Conclusion: The most appropriate FAH measurement method should be selected according to the purpose, considering the advantages and disadvantages of each measurement method. The foot morphology has slight effect on the weight-bearing dorsiflexion ROM and balance ability.