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ObjectivesA pitching motion involves three-dimensional whole body movement. Proper pelvic and trunk rotation movement are important for the prevention of throwing injuries. Given that throwing is not a simple rotation movement, the evaluation of proper motion should reflect muscle strength as well as coordination and pitching motion characteristics. We have devised a throwing rotational assessment (TRA) as a new evaluation of the total rotation angle required for throwing. The purpose of this study was to examine the characteristics of players with throwing disorders compared to a pain-free group using TRA.Materials and methodsThe subjects consisted of 164 high school baseball pitchers who participated in a medical check. Pain-induced tests included an elbow hyperextension test and an intra-articular shoulder impingement test. Pitchers who felt pain in either test were classified into a disorder group (n=61). With the subjects in a position similar to the foot contact phase of throwing, the rotation angles of the pelvis and trunk were measured. All tests were performed in the throwing and opposite directions.ResultsThe disorder group had significantly lower average rotation angles of the pelvis and trunk in the throwing direction and the rotation angle of the trunk in the opposite direction compared to the healthy group.ConclusionTRA reflects the complex whole body rotation movement. Reductions in rotational angles as assessed in TRA may be associated with throwing disorders. TRA is a simple method that may be useful in the early detection of a throwing disorder and could be used in the systematic evaluation during a medical check, as well as during self-check in the sports field.

The changes in lumbar lordosis angle (LL) and sacral slope angle (SS) related to upper limb elevation and thoracic kyphosis angle (TK) in baseball players with spondylolysis remain unclear. Herein, we investigated baseball players with spondylolysis and those without low back pain, comparing LL and SS with upper limb elevation within and between groups and TK between groups. Baseball players with spondylolysis were enrolled as subjects, and baseball players without low back pain were enrolled as controls (n = 8 each). X-rays were obtained in the standing position and with maximal elevation position of the upper limb (elevation position). LL and SS were measured in the standing and elevated positions, and TK was measured in the standing position. LL was significantly larger in individuals with spondylolysis than controls. The SS of the control group was significantly larger in the elevated position than in the standing position, while the SS of the spondylolysis group was not significantly different between positions. SS was significantly larger in the spondylolysis group than in the control group, only in the standing position. Physical therapy for spondylolysis should focus on hyperlordosis alignment in the standing and maximal elevation positions of both upper limbs, sacral hyper-slope alignment in the standing position, and decreased sacral slope motion.

高校女子バレーボール部に実施したメディカルチェックの概要と振り返りをまとめることを第1の目的とした．次にチームの指導者に対してインタビュー調査をおこない，医療者側と指導者側の共通点や相違点を明らかにすることを第2の目的とした．メディカルチェックによって障害の把握ができ，医療機関と学校との連携を促進することができた．インタビューで指導者は早期発見や，教育的観点からも考えていることが明らかになった．, The first objective of this study was to summarize the contents of the medical checkups conducted on the high school women volleyball team. The second objective was to conduct an interview survey with the team's instructors to clarify the similarities and differences between the medical staffs and instructors. The medical checkup enabled us to understand the disorder and to promote cooperation between the medical institution and the school. In the interviews, it became clear that the instructors considered not only early detection but also educational perspectives to be important., 原著(Original paper)

Purpose: The purpose of this study was to compare pitching motion of the professional female baseball pitchers with the male university baseball pitchers focused on the pelvic and thoracic movements. Subjects and methods: The participants were 15 healthy professional female baseball pitchers (11 right-handers and 4 left-handers; age, 21.7 ± 3.2 years; height, 162.5 ± 5.1 cm; weight, 59.0 ± 6.6 kg) and 14 healthy male university baseball pitchers (12 right-handers and 2 left-handers; age, 19.9 ± 0.8 years; height, 176.4 ± 3.0 cm; body mass, 73.1 ± 3.0 kg). Throwing motion was captured by three-dimensional motion analysis system. Kinematic data of the lead hip, pelvis, thorax, and dominant shoulder were collected and the joint angle at maximum external rotation phase and ball release phase were compared. Results: The female baseball pitchers rotated pelvis and thorax more than the male at the maximum external rotation phase and ball release phase (p < 0.05). At the same, the pelvis and thorax of the female baseball pitchers were tilted significantly closer to horizontal plane than the male (p < 0.05). The pelvis and thorax of the male baseball pitchers was tilted to non-dominant lateral side. Conclusions: The results of this study indicate that the pelvic and thoracic movements of the professional female baseball pitchers was different from male university pitchers.

Watanabe, Y, Yamada, Y, Yoshida, T, Matsui, T, Seo, K, Azuma, Y, Hiramoto, M, Miura, Y, Fukushima, H, Shimazu, A, Eto, T, Saotome, H, Kida, N, and Morihara, T. Relationship between physical fitness at the end of preseason and the inseason game performance in Japanese female professional baseball players. J Strength Cond Res 33(6): 1580-1588, 2019-This study examined anthropometric and fitness profiles of Japanese female professional baseball players and investigated the relationship between players' physical fitness and inseason game performance. Fifty-seven players who were registered in the Japan Women's Baseball League (JWBL) participated. Height, body mass, grip strength, back strength, knee extension and flexion strength, hamstring extensibility, vertical jump height, and horizontal jump distance were measured at preseason (February and March) in 2013. Game performance during the 2013 season (March-November) was obtained from official JWBL statistics. Vertical jump height showed significant positive correlations with individual performance records (e.g., total bases [r = 0.551], slugging percentage [r = 0.459], and stolen bases [r = 0.442]). Similar relationships were observed between horizontal jump distance and performance statistics in most cases. By contrast, grip, back, and lower-limb strength, as well as hamstring extensibility were not significantly correlated with game performance. Stepwise regression analysis selected vertical jump height as an independent variable, significantly correlating with several game performance measures (e.g., total bases: adjusted R = 0.257). Also, vertical jump height and body mass index were identified as independent variables significantly associated with stolen bases (adjusted R = 0.251). Maximal jump performance, rather than simple isometric muscle strength or flexibility, is a good performance test that can be used at the end of preseason to predict inseason batting and stolen base performance. Our findings demonstrate the importance of constructing preseason training programs to enhance lower-limb muscular power that is linked to successful inseason performance in female baseball players.

The purpose of this study was to assess the range of motions of the upper and the lower limbs in junior and senior high school baseball players to examine relationships between the range of motions and shoulder injuries caused during throwing motions. Significant differences in the range of motion were not shown for any of the items between the injured and the healthy groups of junior or senior high school students. The height, weight, age, years of baseball experience, and the age of starting baseball indicated a significant difference only for the weight in the injured junior high school group (p

Purpose: The purpose of this study was to investigate the relationship between the standing trunk extension angle and medial elbow injuries. Subjects and methods: The study participants were 90 male baseball pitchers (10–12 years) belonging to youth baseball teams. Pitching elbow injuries were evaluated by an orthopedic surgeon using ultrasound scans and physical examination findings. A single optical three-dimensional motion analysis system was used for the trunk extension measurements, with three-dimensional coordinates captured. The overall, upper, and lower trunk angles were then analyzed. Results: Trunk extension angle during standing trunk extension was significantly smaller among participants who were positive for medial elbow injuries on ultrasound scans (positive: 71.4° ± 10.3°; negative: 75.7° ± 9.2°; t = 2.05, p < 0.05). The upper trunk extension angle was significantly smaller than the lower trunk extension angle among participants who were positive for medial elbow injuries on physical examination (upper: 33.0° ± 6.9°; lower: 41.2° ± 8.2°; t = −2.42, p < 0.05). Conclusions: Trunk extension angle during standing trunk extension is associated with medial elbow injuries. Evaluating the trunk extension angle as multiple segments rather than a single rigid body is valuable.

The purpose of this study was to measure range of motion among professional women baseball players and to identify specific attributes through comparison against university men players. Subjects were 53 professional women baseball players (average age 21.9 ± 2.9 years) and 23 university men baseball players (19.8 ± 0.8 years). Measurement of shoulder external and internal rotation, neck and thoracolumbar rotation, hip internal and external rotation, SLR and HBD revealed sex differences and laterality. Women players had higher lower limb flexibility values compared with men, and like men, demonstrated laterality in range of motion in the limbs and trunk. Findings from this study may provide reference values that can be applied to women’s conditioning programs.

Objective The rotational range of motion (ROM) in the upper extremities, trunk, and lower extremities is important for throwing motion. However, unlike for the shoulders, the differences relating to age and throwing-side in trunk and lower extremity ROMs in baseball pitchers are unknown. This study examined the effects of age and dominance on the ROMs of the trunk and upper and lower extremities. Methods The study included 356 young baseball pitchers aged 9-17 years who participated in off-season baseball camps. The subjects comprised 155 youth pitchers (aged 9-14 years) and 201 high-school pitchers (aged 15-17 years) who were able to throw at full force without pain. The neck, shoulder, trunk, and hip rotational ROMs on the dominant and non-dominant side were measured by well-trained physical therapists. The differences between throwing sides and between age groups were examined using two-way analysis of variance. Results Shoulder external rotation on the dominant side was greater than that on the non-dominant side. Shoulder external and internal rotational ROMs were maintained regardless of age, whereas the trunk rotational ROM significantly increased with age. Conclusions The effects of age and dominance on ROMs of the neck, trunk, and upper and lower extremities in Japanese youth and high-school baseball pitchers were clarified. These data could be used as a specific reference and as target values for the rehabilitation of throwing injuries in young athletes.

投球障害は投球側下肢関節機能低下によって引き起こされることも多く,下肢関節機能の評価は重要である.しかし,投球動作中の下肢における経時的な筋活動パターンは不明なため,筋電図と三次元動作解析装置を用いて検討した.大腿筋膜張筋と中殿筋の筋活動は並進運動直前にピークを示した.長内転筋と大腿直筋の筋活動は非投球側下肢の接地直後にピークを示した.長内転筋は過剰な並進運動の制動と,骨盤の回旋に作用すると考えられる., The evaluation of lower extremity function is important for throwing disorders. The purpose of this study was to investigate the muscle activation patterns around hip during pitching motion by three-dimensional motion analysis system synchronized with surface electromyography. The timing of peak tensor fasciae latae and gluteus medius activities was before maximum knee elevation of non-dominant lower extremity in wind-up phase. The timing of peak adductor longus(AL) and rectus femoris(RF) activities was immediately after non-dominant foot contact. This study suggested that AL could put a brake on moving body to the catcher excessively and help the pelvis rotating in the direction of throwing.

経年的な可動域の変化と障害の状況を知る目的で,野球肘検診を実施した.対象は軟式野球部1年生63名とし,肩・肘関節の疼痛の有無を質問し,可動域測定を行った.3年生時も52名を対象として検診を実施し,入学時と比較・検討した.結果,3年生時では肩・肘関節に疼痛を訴える選手が増加していた.肩関節外旋・内旋(2nd)および股関節内旋可動域は有意に減少したが,頚部回旋は有意に増加していた., The purpose of this study was to investigate the change of range of motion in junior high school baseball players. The subjects were 63 new junior high school baseball players belonging to school baseball team. Physical examinations were performed by physical therapists. In the third-year student, 52 players were checked as well. There were statistically less in the third-year student in average external and internal rotation with the arm in 90 degrees of abduction, internal rotation of the hip joint. Average neck rotation was statistically greater in the third-year student., 原著(Original investigation)

中学校硬式野球部の新入部員62名(入部前の 野球歴あり群41名・野球歴なし群21名)に対して,肘関節への超音波検査を併用した野球肘検診を実施し,その有用性を検討した。野球歴あり群42名のうち18名に内側の異常所見を,5名に外側の異常所見である上腕骨小頭の離断性骨軟骨炎(Osteochondritis dissecans; 以下OCD)を認めた。内側に検診時に圧痛を認めた症例は4例のみであり,超音波検査は内側型野球肘障害の既往も検出する。また,上腕骨小頭のOCD5名のうち4名は検診時に無症状であった。今回の結果から,超音波検査を用いた野球肘検診は早期に症状が発現しにくい外側型野球肘の早期診断に特に有用であると考える。, The purpose of this study was to evaluate the efficacy of the baseball elbow medical check using sonography among junior high school baseball players. 62 new junior high school baseball players were participated. 41 players were experienced and 21 players were inexperienced students. Eighteen players were diagnosed as medial type of the baseball elbow in 41 experienced students where only 4 of them had the present tenderness of the elbow and 15 of them had past history of throwing pain of the elbow. As for lateral type of the baseball elbow, sonography showed that 5 of the experienced players had osteochondritis dissecans (OCD) of the capitellum where only one of them had present and past pain of the elbow. Medical check using sonography is useful for detecting baseball elbow injury, especially for detecting OCD., 原著(Original investigation)

Yosuke Yamada,1,2 Daichi Yamashita,2,3 Shinji Yamamoto,2,3 Tomoyuki Matsui,4 Kazuya Seo,4 Yoshikazu Azuma,4 Yoshikazu Kida,5 Toru Morihara,5 Misaka Kimura1 1Laboratory of Sports and Health Science, Kyoto Prefectural University of Medicine, Kyoto, Japan; 2Research Fellow, Japan Society for the Promotion of Science, Tokyo, Japan; 3Graduate School of Human and Environmental Studies, Kyoto University, Kyoto, Japan; 4Department of Rehabilitation, Graduate School of Medical Science, Kyoto, Prefectural University of Medicine, Kyoto, Japan; 5Department of Orthopedics, Graduate School of Medical Science, Kyoto Prefectural University of Medicine, Kyoto, Japan Abstract: The aim of the study was to examine the relationship between pitching ball velocity and segmental (trunk, upper arm, forearm, upper leg, and lower leg) and whole-body muscle volume (MV) in high school baseball pitchers. Forty-seven male high school pitchers (40 right-handers and seven left-handers; age, 16.2 ± 0.7 years; stature, 173.6 ± 4.9 cm; mass, 65.0 ± 6.8 kg, years of baseball experience, 7.5 ± 1.8 years; maximum pitching ball velocity, 119.0 ± 9.0 km/hour) participated in the study. Segmental and whole-body MV were measured using segmental bioelectrical impedance analysis. Maximum ball velocity was measured with a sports radar gun. The MV of the dominant arm was significantly larger than the MV of the non-dominant arm (P < 0.001). There was no difference in MV between the dominant and non-dominant legs. Whole-body MV was significantly correlated with ball velocity (r = 0.412, P < 0.01). Trunk MV was not correlated with ball velocity, but the MV for both lower legs, and the dominant upper leg, upper arm, and forearm were significantly correlated with ball velocity (P < 0.05). The results were not affected by age or years of baseball experience. Whole-body and segmental MV are associated with ball velocity in high school baseball pitchers. However, the contribution of the muscle mass on pitching ball velocity is limited, thus other fundamental factors (ie, pitching skill) are also important. Keywords: pitching, ball velocity, muscle volume, body composition, trunk, upper and lower extremities

Publisher Summary Studying refractory periods, occlusion, and inhibition using somatosensory-evoked potentials (SEPs) could explore the complex mechanisms of these synaptic connections. This chapter presents a series of SEP experiments started from the anecdotal observation that the amplitude of common peroneal nerve (CPN)-SEP was smaller than that of the posterior tibial nerve (PTN)-SEP or sural (SN)-SEP. This was contrary to the “intuitive” expectation that CPN-SEP with stimulation at the knee would produce larger amplitude response than PTN stimulation at the ankle, because CPN stimulation at the popliteal fossa activates larger fibers receiving greater peripheral receptors than the PTN stimulation at the ankle. The chapter examines the interactions of mixed nerve (PTN) and sensory nerve (SN), and also sensory (SN) and sensory (saphenous) nerves.

膝関節へのテーピングが,健常成人の下肢の運動機能に及ぼす影響を動作解析装置を用いて評価した。健常成人8名に対して,35cmの段差を踏み上がらせて膝関節90度屈曲位で10秒間静止させた姿勢の関節角度,関節モーメント仕事量を床反力計および三次元動作解析を用いて計測した。関節角度は,股関節・膝関節・足関節ともに有意差を認めなかったが、関節モーメント仕事量は膝関節においてテーピング群が有意に増大した。テーピング貼付時の膝関節の肢位,貼付方法,テープ素材の影響に加え,テープ貼付による皮膚を介した固有感覚受容器を活性化が,関節の安定性向上に寄与した可能性がある。健常人に対する膝関節へのテーピングは,膝関節の安定性と運動能力の向上に寄与するものと考える。, The objective of this study was to examine the effects that knee joint taping has on motor functions. In this study we used eight healthy adult subjects.We had the subjects stand still for 10 seconds while they maintained the position of having their hip joint and knee joint being 90 degrees of each other by stepping on a 35cm high box that was on top of a force plate.The workload of the joint moment increased significantly in the knee joints from the taping in the taping group. We concluded that the leg position of the taping, the method of taping, and the variety of materials we used had some effect on the results., 原著(Original investigation)