Abstract
The function of M. adductor longus and M. adductor magnus in the movement of the hip joint are electromyographically investigated. The results obtained are as follows.
I M. adductor longus
1. The muscle is a flexor for the first 50 degrees of movement. If the thigh flexed against resistance took a slightly inward direction, the electromyographic discharge ceased before 50 degrees of movement. Conversely, if the resistance took a slightly outward direction, the discharge appeared beyond 50 degrees.
The muscle acts for flexion at any vertical plane until the 50 degree horizontal angle is reached.
2. The muscle does not act for extension of the thigh.
3. The muscle acts for adduction of the thigh at any position of sagittal plane. Especially, at the flexed position the muscle is a prime mover of the thigh adduction and even at the extended position when the resistance is increased, the muscle come to act for adduction.
II M. adductor magnus
1. The muscle does not act for flexion of the thigh.
2. The muscle acts during thigh extension. Particularly, the extending power increases in proportion as the thigh elevation increases. The muscle acts for exten-sion at any vertical plane until the 40-50 degree horizontal angle is reached.
3. When the thigh is in extension, the muscle works strongly for adduction in any position, but if the thigh is elevated beyond 10 degrees, the muscle does not work for adduction.
