Clinical Outcomes After Posterior Lumbar Interbody Fusion: Comparison of Cortical Bone Trajectory and Conventional Pedicle Screw Insertion

Study Design:This study is a retrospective cohort study using prospectively collected data.Objective:To compare the effectiveness of posterior lumbar interbody fusion (PLIF) using the cortical bone trajectory (CBT) and conventional pedicle screw (PS) techniques.Summary of Background Data:There are few published studies to date comparing PLIF using CBT technique with PLIF using the conventional PS technique.Methods:We studied 119 consecutive patients who underwent single-level PLIF between 2010 and 2014 with a minimum 12-month follow-up. Forty-two patients underwent CBT-PLIF (the CBT group) and 77 underwent conventional PS-PLIF (the PS group). Clinical outcomes were assessed by the Japanese Orthopaedic Association Back Pain Evaluation Questionnaire (JOABPEQ) and visual analog scale (VAS). To assess perioperative pain, a 6-point Numeric Rating Scale score and the total amount of diclofenac sodium suppositories used were recorded. The operative time and blood loss were recorded. Muscle damage was evaluated by serum creatine kinase concentrations. Fusion status was evaluated using 3-dimensional computed tomography 12 months postoperatively. We used inverse probability of treatment weighting based on the propensity score to reduce confounding factors.Results:There were no significant between-group differences in operative time or fusion rates, whereas the CBT group experienced significantly less blood loss, lower postoperative creatine kinase levels, less diclofenac sodium suppositories, and lower Numeric Rating Scale scores than the PS group did. The change in the JOABPEQ subdomain score for social life function 1 month postoperatively was the only significantly different factor among the JOABPEQ and VAS scores.Conclusions:Both procedures were comparable in terms of clinical outcomes and fusion rates, but CBT-PLIF provided the additional benefits of less blood loss, less intraoperative muscle damage, less perioperative pain, and earlier recovery to normal activities.