The<unk>  (NCS) results most commonly from the compression of the left renal vein (LRV) between the abdominal aorta (AA) and superior mesenteric artery (SMA), although other variants exist. The name derives from the fact that, in the sagittal plane and/or transverse plane, the SMA and AA (with some imagination) appear to be a<unk>  crushing a nut (the renal vein). Furthermore, the venous return from the left gonadal vein returning to the left renal vein is blocked, thus causing testicular pain (colloquially referred to as "nut pain"). There is a wide spectrum of clinical presentations and diagnostic criteria are not well defined, which frequently results in delayed or incorrect diagnosis. This condition is not to be confused with superior mesenteric artery syndrome, which is the compression of the third portion of the duodenum by the SMA and the AA.
Nutcracker syndrome
Wieacker syndrome
MASS syndrome
Emmonsiosis
Pellegrini–Stieda syndrome
Riddoch syndrome
Aortoenteric fistula
EAST syndrome