Background: Hara physical test is useful for evaluating baseball players with throwing disorder in order to determine the imbalance between their rotator cuff and shoulder girdle muscles. There are few reports of medical checkups conducted for high-school baseball players using Hara physical test. The purpose of this study was to elucidate the relationship between Hara physical test and throwing disorders in high-school baseball players.
Methods: Six hundred and ninety-nine baseball players were assessed using Hara physical test (11 items). All participants answered questionnaires on throwing disorders before the medical checkup. The correlation between throwing disorders and physical test was analyzed by logistic regression analysis. Furthermore, the relationship between impingement sign and hyper external rotation test, which are pain test in Hara physical test and other 9 item was investigated by logistic regression analysis.
Results: One hundred and ninety-one players (27%) had throwing disorders. According to the logistic regression analysis, throwing disorder had a significant correlation with impingement sign and hyper external rotation test (HERT) in Hara test (odds ratio; 4.51 and 2.76, and p value; < 0.001 and 0.003, respectively). Moreover, HERT was significantly correlated with horizontal flexion test (HFT) and manual muscle testing of supra supinates tendon (MMT-SSP) (odds ratio; 4.55 and 7.28, and p value; < 0.01 and 0.03, respectively).
Conclusion: Impingement sign and HERT were significantly related to throwing disorder. Furthermore, HFT and MMT-SSP were significantly related to HERT. These four tests were especially useful for medical checkup of high-school baseball players.