This is an uncommon finding on CT KUB, for a common history of renal-type pain.

Lumbar hernias are rare hernias of the posterior abdominal wall, most commonly occurring in 50-70 year olds, often male. Superior lumbar hernias (Grynfeltt-Lesshaft hernia) are the more common type, occuring through the superior lumbar hernia. Larger hernias can contain intra- or retroperitoneal structures.

In this patient, urine MCS and blood tests were normal and he was managed with analgesia.