Comparison of minimally invasive and open transforaminal lumbar interbody fusion in the treatment of single segmental lumbar spondylolisthesis: minimum two-year follow up

Background: Compare the efficacy and safety of minimally invasive and open transforaminal lumbar interbody fusion (TLIF) in the treatment of single segmental lumbar spondylolisthesis. Methods: From 2010-01 to 2015-10, in total, 167 patients with single segmental spondylolisthesis treated by TLIF were included, 79 cases in minimally invasive TLIF (MI-TLIF) group and 88 cases in open TLIF group. The peri-operative parameters of operative time, estimated blood loss and length of postoperative hospital stay was recorded, as well as complications. Visual Analogue Scale (VAS) of low back pain and leg pain, and Oswestry Disability Index (ODI) were used to assess the pain and functional outcomes at pre-operatively, 3 months/1 year/2 years/5 years after operation. The radiographic parameters of posterior height of the intervertebral space and segmental lordosis were measured too. Results: No significantly difference was found at baseline characteristic data of age, gender ratio, the percentage of degenerative and isthmic spondylolisthesis, the percentage of slip, and segmental distribution between MI-TLIF and open TLIF groups. MI-TLIF group had less estimated intra-operative blood loss (163.7 +/- 49.6 mL) than open TLIF group (243.3 +/- 70.2 mL, P<0.001) and had shorter post-operative hospital stay (5.8 +/- 1.4 days) than open TLIF group (7.3 +/- 2.9 days, P<0.001). Both MI-TLIF and open TLIF can significantly reduce the VAS of low back pain, VAS of leg pain, ODI, and improve the posterior height of the intervertebral space and segmental lordosis, but no significantly difference was found of them between two groups. Conclusions: Our study suggests that MI-TLIF is a safe and effective choice in the treatment of lower grade lumbar spondylolisthesis (grade II or less), and it has advantages of less blood loss, postoperative hospital stay when compared to open TLIF.