What Causes Severe Backache?

Hello, my 46 year old husband has been having posterior flank pain in the thoracic area. He recently has had some kidney issues , high creatinine due to probable excessive ibuprofen use( due to shoulder pain). He is a construction worker who is in good shape for his age. He had seen a urologist and a nephrologist during this time. They did diagnose crystals and some stones but no treatment other then stopping the ibuprofen use. He also has had a laminectomy about 15 years ago followed by the following year of spinal decompression. This pain now is higher and unlike the type of back pain he has experienced. He hasn’t seen a chiropractor for a few years and is scheduled tomorrow for an evaluation and/ or adjustment. I am a massage therapist retired and did work on his posterior muscle groups but hesitated because I felt if this was related to the kidneys I didn’t want to complicate matters. In your opinion, what’s the most likely cause? Thanks for your consideration, Lou