Why do All Muscles Cross a Joint?
All muscles cross the joints. If they do not cross a joint, it means they will not be able to move our body parts. If any muscle starts at the elbow and ends up near the wrist then the hand becomes totally solid enough that it cannot be moved properly. The muscles that are connected to the joint bones are called tendons. The main function of the muscle is to move our body parts. The human skeleton cannot be moved without the help of muscles. Without the muscle help, our body cannot be moved from one place to the other, our eyes may not blink, the food may not be digested, we may not breathe, the heart pumping may not occur, we may not smile, urination and defecation may not be possible and our nose may not be used for smelling.
The major functionality of muscle is to relax and contract. The muscle pairs called synergist and antagonist slide on each other and make the movement possible. When the muscle is contracted, it tightens and become shortened. If the muscle relaxes, it becomes longer and small. The muscle fibers pull in order to make a movement. The muscle fibers slide on each other while working. The sliding function is obtained from the food we eat.
If the muscles are connected in between the two ends of the bone without crossing at the joint, the movement of the knee cannot happen. This is because the muscle will not be able to shorten or lengthen, if it ends up in the joint. If we have to bend our knees it is necessary for the muscles to cross the joints. The thigh muscles have to cross the knee joint and travel behind the knee to get attached at its back. Then, if we tighten the muscle, the knee will bend freely without any problem. Thus, all muscles cross a joint.