This study compared the 9-year outcome of 124 patients that were randomized to two different treatments. Patients with chronic low back pain received either instrumented lumbar fusion (one-third of these patients were re-operated) or cognitive intervention and exercises (one-third of these patients had been crossed over and operated). At the 9-year follow-up, no significant differences were produced between the two groups in the primary (Oswestry Disability Index) or the secondary (pain, fear-avoidance beliefs, trunk muscle strength, medication, and return to work) outcome measures.