152 patients, aged 20 to 55 years, suffering from chronic low back pain (CLBP) were randomized to compare the long-term efficacy of total disc replacement to lumbar spinal fusion, over 5 years. Patients were assessed using global assessment (GA) of back pain, VAS low back pain, disease-specific pain, disability measured by Oswestry Disability index (ODI), EQ-5D, SF-36, and VAS leg pain. The evidence presented in this study demonstrated that total disc replacement and lumbar spine fusion resulted in improved chronic low back pain outcomes; however more than twice as many total disc replacement patients reported being totally pain free after 5 years. Total disc replacement patients also had significantly superior outcomes in nearly all measured variables, with comparable rates of reoperation and complications.