Early Clinical Outcome of Lumbar Spinal Fixation With Cortical Bone Trajectory Pedicle Screws in Patients With Osteoporosis With Degenerative Disease.

This cohort study aimed to elucidate early surgical outcomes after midline lumbar fusion (MidLIF) with cortical bone trajectory (CBT) screw fixation compared with transforaminal lumbar interbody fusion (TLIF) using traditional pedicle screw (TPS) fixation for lumbar degenerative disease (LDD) in patients with osteoporosis. The authors randomly assigned 70 patients with osteoporosis who had LDD at 1 or 2 adjacent vertebral levels to undergo either MidLIF with CBT (CBT group) or TLIF with TPS fixation (TPS group) from February 2015 to March 2016. Pre- and postoperative lumbar Japanese Orthopaedic Association (JOA) scale scores were assessed and radiographic measurements on dynamic plain radiographs and computed tomography images were analyzed. The final data analysis included 31 patients in the CBT group (mean age, 73.42±6.74 years; t-score, -2.94±0.75) and 32 patients in the TPS group (mean age, 74.84±5.37 years; t-score, -2.92±0.66). Mean JOA score improved significantly in both groups, although no intragroup differences of JOA score improvement were found at the latest follow-up evaluation (P>.05). In addition, significantly higher rates of screw loosening (28.13% vs 6.5%, P=.03) and the amount of subsidence (3.01±0.52 vs 2.49±0.45 mm, P=.02) were found in the TPS group. Rate of radiographic fusion of both groups showed no statistical difference. Both groups of patients achieved a similar rate of radiographic fusion at the 1.5-year follow-up and experienced similar intra- or postoperative complications and postoperative recovery. The MidLIF with CBT screw fixation for short-level lumbar fusion in patients with osteoporosis provided improvement of clinical symptoms comparable to that of TLIF using traditional TPS fixation. In addition, statistically significant lumbar stability was found in the CBT group compared with the TPS group. [Orthopedics. 2019; 42(5):e465-e471.].