Comparison between posterior dynamic stabilization and posterior lumbar interbody fusion in the treatment of degenerative disc disease: a prospective cohort study

BACKGROUND: Few studies compared radiographic and clinical outcomes between posterior dynamic stabilization (PDS) and posterior lumbar intervertebral fusion (PLIF) in treating degenerative disc disease (DDD). METHODS: A total of 176 consecutive patients who underwent posterior instrumented spinal surgery for degenerative disc disease between January 2007 and January 2009 were prospectively divided into two groups—PDS and PLIF. All patients included in the analysis were followed up for 3 years. Demographic distribution, perioperative complications, and radiographic and clinical outcomes were compared between the two groups. RESULTS: The amount of intraoperative blood loss and drained volume was significantly greater in the PLIF group compared with the PDS group (881.1 ml versus 737.4 ml, p = 0.004). The length of stay of patients who had PLIF surgery (20.9 days) was significantly longer (p = 0.033) than that of patients who underwent PDS surgery (18.9 days). Patients with PLIF surgery had higher total costs than those with PDS surgery (US$12826.8 versus US$11654.5, p = 0.002). No statistically significant differences existed in back visual analogue scale (VAS), leg VAS, or Oswestry disability index (ODI) scores between the PDS and PLIF groups of patients at each time point. CONCLUSIONS: Compared with PLIF, PDS have advantages on blood loss, length of stay in hospital, total charges, and radiographic outcomes, but no advantages on leg and back VAS or ODI scores. High-quality randomized controlled trials are still required in the future.