Most ectopic kidney patients have their kidneys located at the posterior part of the navel, with two renal areas on the back. Some ectopic kidney patients may have a lower kidney position than the normal population, located in the pelvic and abdominal cavity, so it is usually necessary to judge the specific position of the kidney through ultrasound.

1. Normal Condition: The surface projection of the kidney is on the posterior back, with the upper limit at the 11th lumbar vertebra level and the lower limit at the 3rd lumbar vertebra level, 2.5 cm from the inner side, and the lateral line is the posterior median line;

2. Ectopic Kidney Patients: If a patient has an ectopic kidney, the kidney may be lower than the normal kidney. In some cases, the patient’s kidney is located in the pelvic or abdominal cavity, above or below the navel. When an ectopic kidney occurs, it is necessary to consider whether there are other malformations at the same time, such as ureteral tortuosity and other ureteral malformations or pelvis malformations, which is the change in renal morphology. At the same time, it is necessary to consider the functional changes of the kidney, such as whether the function of the ectopic kidney is the same as that of the normal kidney, and whether the glomerular filtration rate is within the normal range. Most ectopic kidney patients are located in the renal area. If an ultrasound examination is performed, it may be found that there is no normal kidney in the renal area, or only one normal kidney, at this time, a radioactive isotope renal scan is needed to determine the position of the kidney.

The kidneys of a fetus are initially located in the pelvic cavity. As the body develops, the kidneys gradually rise and reach their normal position, which is behind the navel and the back. If an abnormality occurs during the process of body development, it can lead to an abnormal kidney position or incomplete kidney development, which may have a greater impact on the body.