A small lump of muscle protruding from the inside of the calf is an abnormality and may be related to a myofascial hernia. Each muscle in the calf is wrapped in myofascia, and all of the muscles are wrapped in deep fascia on the outside. The myofascia and the deep fascia work together to bind the calf muscle fibers and keep them in a normal shape. If trauma or surgery to the calf destroys these structures, a myofascial hernia will form when the calf muscle loses its binding. Small hernias have no effect on the contractile function of the calf muscle, but can be aesthetically displeasing. If the hernia is large, it will cause a decrease in the tension of the calf muscle, thus affecting the contraction function of the calf muscle. If there is a small pile of muscle herniation on the inner side of the calf, it is recommended that the patient go to the hospital and under the guidance of the doctor for regular treatment.