Spinal cord physical movement function

(1) flexor reflection and opposite extensor reflection

When the skin of the limb is damaged, the side limb has a flexion movement, and the joint flexion is contracted and the extension muscles are relaxed. The flexor reflex is protective, making the limbs flexion and avoiding damage to stimulation. The intensity of flexor reflection is related to the stimulus strength. For example, the weak stimulation of the foot only causes flexion of the ankle joint; when the stimulus intensity is increased, the knee and marrow joint can also be flexion. If the stimulation strength is greater, the opposite limb stretching reflection can occur on the basis of the alien limb reflection, which is called the opposite extensor reflection. The side of the animal flexion and straighten the opposite limbs to help support weight and maintain their posture. The center of the flexor reflection and the opposite extensor reflection are in the spinal cord.

(2) Advings reflection

When the skeletal muscle is stretched by external force, it can reflect the contraction of the same muscle that is pulled, which is called a tension reflection. Due to the different forms of pulling, the reflection effect of muscle contraction is also different, so the reflection can be divided into two types: tendon reflection and muscle tension.

1. tendon reflection; tendon reflection refers to the reclutorated reflection that occurs when the tendon quickly pulls the tendon. For example, the tetramidis tendon below the knee joint and the muscles are pulled, then a rapid contraction occurs once, called knee jump reflection; A rapid contraction of muscle occurs, called Achilles tendon reflection. The characteristic of tendon reflection is that when hitting the tendon, the muscle shuttles (a body feel) in the muscles are almost pulled at the same time, and the impulse to enter the center will almost cause the muscle's motor neuron to excite, so it should be timely The muscle fiber of the muscle occurs almost at the same time. Clinically, tendon reflexes are often checked to understand the function of the spinal cord. If a tendon reflex is weakened or disappeared, it is prompted to be damaged by the spinal cord function of the corresponding section; Constraine.

2. Muscle tension; the skeletal muscle of the spinal animal still maintains a certain muscle tension, called muscle tension, and it is also a kind of reflection. Muscle tension occurs due to the slowly pulling of the muscles. The entire muscle is in a continuous and weak contraction state to prevent the muscles from being stretched. The significance of muscle tension is to maintain the posture of the body without showing obvious movements. During the occurrence of muscle tension, different muscle fibers in the same muscle are shrinking, so it can maintain muscle tension and not fatigue. Under normal circumstances, the skeletal muscles of humans and animals are also in a continuous and weak contraction state when there is no obvious exercise manifestation, and the extension and flexion muscles have a certain tension. However, in the upright posture, the tension of extension is in the main position; because of the effects of gravity, the joints that support weight tend to be bent by the weight due to the impact of gravity. Make the muscles of the extensor tension and maintain an upright posture with the bent of the joint. Due to the continuous action of the joints, muscle tension continues to occur.

Tip: The content of this article is for reference only, please refer to the consultation results of regular hospitals!