What does it mean after passing kidney stones:" there is anterior rotation of the left renal access congenital?"

Congenital anomaly: The fetal kidneys undergo a 90° rotation around their longitudinal axis during their ascent from the pelvis before they reach their final position by the end of the 8th week of fetal life. Abnormal rotation may partially obstruct the junction of the kidney & ureter, the tube that leads to the bladder, increasing the risk of having kidney stones & upper urinary tract infections.