Supplementary stabilization with anterior lumbar intervertebral fusion - A radiologic review

Study Design. A radiologic assessment of the success of anterior lumbar interbody fusion (ALIF) using thin-section computerized tomography (CT) was performed. Objective. To assess the effect of different types of posterior stabilization on the fusion rate of ALIF. Summary of Background Data. Thin-section CT has shown a higher rate of pseudarthrosis with ALIF than previously reported with standard radiologic methods. Cadaveric studies have shown that posterior stabilization would increase stiffness of the motion segment and is likely to enhance the rate of fusion with ALIF. To our knowledge, the results of thin-section CT of ALIF, with and without posterior stabilization, has not been reported previously. Methods. Patients with discogenic back pain confirmed by diskography underwent ALIF surgery, either as a stand-alone procedure or with posterior stabilization, using translaminar, unilateral pedicle, or bilateral pedicle screws. The 4 cohorts were followed up prospectively, and thin-section CT was used to assess interbody fusion. Results. The fusion rate for stand-alone ALIF was 51%, for patients with supplementary stabilization with translaminar screws 58%, with unilateral pedicle screws 89%, and with bilateral pedicle screws 88%. A significant difference in the fusion rate was found when ALIF was combined with pedicle screw stabilization (P < 0.01). Conclusion. The addition of pedicle screw fixation at ALIF produces a significant increase in the rate of interbody fusion.