Nikolai Bogduk

Although posterior lumbar interbody fusion (PLIF) is regarded as an effective treatment for spondylolisthesis, few studies have reported comprehensive, long-term outcome data, and none has investigated the incidence of deterioration of outcomes. To determine and compare the success rates and long-term stability of outcomes of open PLIF and minimal-access PLIF in the treatment of radicular pain and back pain in patients with spondylolisthesis. Forty-three patients were followed for a minimum of 3 years. They completed a Short-Form Health Survey and visual analog scores for back pain and leg pain and underwent lumbar spine radiography. Outcomes were compared with baseline data and 12-month data. Surgery succeeded in reducing listhesis and increasing disc height, but had little effect on lumbar lordosis or the angulation of the segment treated. At 12 months after surgery, listhesis was reduced, disc height was increased, leg pain was reduced or eliminated, and physical functioning restored. Back pain was less often relieved. These outcomes were largely maintained over the ensuing 2 years. Only 5% to 10% of patients reported deterioration in their relief of pain. Depending on the definition adopted for success, the long-term success rate of PLIF may be as high as 70%. For the relief of leg pain, the success rates of open PLIF (70%) and minimal-access PLIF (67%) for spondylolisthesis are high and durable in the long-term. PLIF is less often successful in relieving back pain, but the outcomes are maintained. The outcomes of open PLIF and minimal-access PLIF were statistically indistinguishable.