Hattori Hiroshi, Akasaka Kiyokazu, Otsudo Takahiro, Sawada Yutaka, Hall Toby
School of Physical Therapy, Saitama Medical University, Moroyama 350-0496, Japan.
Department of Physical Therapy, Saitama Medical University Graduate School of Medicine, Moroyama 350-0495, Japan.
Healthcare (Basel). 2023 Feb 15;11(4):586. doi: 10.3390/healthcare11040586.
The harder the forearm flexor-pronator muscles (FPMs) relative to the ulnar collateral ligament (UCL), the less likely it is for UCL laxity to occur with repeated pitching. This study aimed to clarify what selective contraction of the forearm muscles makes FPMs harder relative to UCL. The study evaluated 20 elbows of male college students. Participants selectively contracted the forearm muscles in eight conditions under gravity stress. The medial elbow joint width and the strain ratio indicating tissue hardness of the UCL and FPMs during contraction were evaluated using an ultrasound system. Contraction of all FPMs (in particular flexor digitorum superficialis [FDS] and pronator teres [PT]) decreased the medial elbow joint width compared to rest ( < 0.05). UCL hardens due to the contraction involving the FDS muscle ( < 0.05). FPMs harden due to the contraction of flexor carpi ulnaris (FCU) and FDS ( < 0.05). In the ratio of strain ratio UCL/FPMs, there was no significant difference between rest and each contraction task ( > 0.05). However, contractions composed of FCU and PT tended to harden FPMs relative to the UCL. FCU and PT activation may be effective in UCL injury prevention.
相对于尺侧副韧带（UCL），前臂屈肌-旋前肌（FPMs）越强，反复投球时UCL松弛的可能性就越小。本研究旨在阐明前臂肌肉的何种选择性收缩会使FPMs相对于UCL更强。该研究评估了20名男性大学生的肘部。参与者在重力负荷下的八种情况下选择性收缩前臂肌肉。使用超声系统评估收缩过程中内侧肘关节宽度以及表示UCL和FPMs组织硬度的应变率。与休息时相比，所有FPMs（特别是指浅屈肌[FDS]和旋前圆肌[PT]）的收缩均使内侧肘关节宽度减小（P<0.05）。涉及FDS肌肉的收缩会使UCL变硬（P<0.05）。尺侧腕屈肌（FCU）和FDS的收缩会使FPMs变硬（P<0.05）。在应变率UCL/FPMs的比值中，休息与各收缩任务之间无显著差异（P>0.05）。然而，由FCU和PT组成的收缩倾向于使FPMs相对于UCL变硬。激活FCU和PT可能对预防UCL损伤有效。
