The quadriceps femoris muscle is the anterior skeletal muscle of the thigh. Since it consists of four different parts (called muscle heads), it is often also called something colloquial four-headed thigh muscle, four-headed leg extensor or quadriceps.
It is more than 150 cm² wide on average and is therefore one of the strongest muscles in the human body. Due to its width, it significantly shapes the lateral contours and the front of the thigh and gives them their shape. If the quadriceps is affected in its function, this can have a significant effect on the entire movement function while walking and standing.
The quadriceps is also referred to as a four-headed leg extensor because it is the only extensor muscle of the knee joint. For this reason, it plays a crucial role in almost all the movements in which the legs are needed. An extension of the knee is necessary when walking or getting up from a sitting or lying position, but also when climbing stairs. In addition, the quadriceps femoris muscle prevents the knee joint from buckling when standing or walking.
It also strengthens and supports the hip joint and has a significant effect on the rotation of the knee joint. This means that he also has influence on movements that take place in the lower part of the legs. If the quadriceps is injured or impaired, this leads to serious disturbances of the movement sequence. These can lead in a small form that walking or standing is difficult. In case of a severe failure of the quadriceps femoris muscle, however, it can also happen that the leg on the knee joint collapses completely and the affected person is unable to load it successfully. In other cases, the quadriceps femoris muscle contracts uncontrollably, which also leads to disturbed movements.
However, in addition to the functions necessary for the movements, the quadriceps femoris muscle also has protective functions: when the knee is stretched, the quadriceps prevents the surrounding tendons, nerves, and tissues from being pinched between the patella and the thighbone by responding to the proper muscle.
The four-headed thigh muscle can be disturbed by external influences as well as by diseases of the body (such as the intervertebral discs) in its function. Typical injuries of the quadriceps are strains of the individual muscle heads that can occur, for example, due to sports overload or accidents. These usually manifest in pain that limits mobility. Depending on the severity and nature of the injury, the discomfort and limitations may last for several days to weeks.
The quadriceps, however, are also disturbed by herniated discs or strokes affecting or removing the nerve roots L3 and L4 or the patellar tendon reflex (PSR). In this case, less pain than numbness and paralysis occur. As a result, the quadriceps relaxes or contracts only in an uncontrolled manner, so that it is no longer possible, or very difficult, to carry out the movements that are controlled by it.
The rectus femoris muscle is one of the shortest muscles in the body. For this reason, he is most prone to injury from all human muscles - which ultimately affects the entire four-headed thigh muscle. Because if the rectus femoris muscle shortens over time, it also affects the entire length of the quadriceps. A progressive shortening of the quadriceps femoris muscle can be counteracted by regular stretching exercises in which the foot is slowly and gently pulled back to the buttocks again and again.Tags: