A jump in the lumbar kidney may be caused by several reasons: 1. It may be caused by a spasm of the lumbar muscles here. This condition is often seen when patients do excessive forceful movements against the lumbar region, such as lifting heavy objects or running and jumping. This may cause a transient spasm of the muscles here, which may result in a continuous throbbing of the muscles afterwards; 2. This condition may be caused by an infection in this area. If there is a focal point of infection under the skin, there may be redness and swelling, fever, pain, and throbbing pain, that is, throbbing pain. For example, a high lumbar disc herniation in the lumbar region may produce paroxysmal radiating pain in this area due to the stimulation of the posterior branch of the spinal nerve; 4. This condition may also be caused by overexertion. If the patient does excessive exercise and labor for the trunk, it may cause muscle fatigue in this area, which in turn may cause the above symptoms.