Hello and welcome dr.wan Well ..according to you the pt.had undergone decompression therapy. Sometimes after surgery the pain still persists of has many. Causes like .failed back syndrome .epidural fibrosis( the formation of scar tissue near the nerve root, can put pressure on the nerve roots and thereby cause pain. Typically, symptoms associated with epidural fibrosis appear about 6 to 12 weeks after back surgery. Sometimes patients experience good pain relief early on after their surgery, but as the scar tissue slowly forms, the pain relief diminishes and leg and back pain recurs or increases. ). .failure of fusion He should continue the medication And physiotherapy for back muscles. If not improves then MRI will be advised to asses further. Hope you d understand. Thanks Bye.