Thanks for the query. Back pain
may be due to disc degeneration. Where is the location? Also its important to know the level of the painful disc. You can not go on fusing the spine without knowing the exact pain source. Also he is long standing diabetic and it can cause this pain. Initially try to control pain with medicine (Antiinflammatory, muscle relaxants and if required pregabalin
) and physiotherapy
modalities such as IFT, manual therapy. I doubt about the need for the fusion surgery. I would suggest to get him examined by a spine specialist. Also sometimes if we can pinpoint the pain generator then we can give him local injection blocks. Thanks.