Comparison between Minimally Invasive versus Open TLIF in Treatment of Spondylolisthesis
Authors: Shaker Hisham , Taha Ahmed , Aboyamn Wael , Hesham Taher , El Besy Sherif , Khattab Mohamed 
Published: April 2016

Introduction Fusion has gained popularity for surgical treatment of adult spondylolisthesis in patients with chronic persistent pain. Several fusion methods have been reported for adult isthmic and degenerative spondylolisthesis via various techniques including minimally invasive and traditional open surgery. However, the choice of lumbar fusion technique must be individualized based on the clinical needs of each patient, the surgical outcomes for each procedure based on published literature, and the individual skills and the surgeon's preference. Much has been reported about the advantages of each approach. The present study was undertaken to evaluate retrospectively the results obtained in patients undergoing mini-TLIF compared with open TLIF, with a goal of helping in the selection of treatment options. We present the clinical and operative results obtained during the postoperative period. Objective To evaluate the results of minimally invasive versus open TLIF in adult lytic and degenerative spondylolisthesis. Methods Between November 2012 and August 2015, 85 consecutive patients underwent minimally invasive transforaminal lumbar interbody fusion (mini-TLIF) (group I) and 49 consecutive patients underwent open TLIF(group II) at Agouza Spine Surgery Center Of Military Forces, Cairo, Egypt. The mean follow-up periods were 18.2 and 20.4 months, respectively. Results The mean age was 51,16+12.76 in mini-TLIF AND 50,67+11.33 in open TLIF with sex distribution (41/44) and (24/25) male to female in mini-TLIF and open TLIF respectively. The mean operative time in mini-TLIF was 190.5 minute and 153.5 minute in open TLIF and the difference was statistically significant. The mean blood loss was 168ml and 476ml in mini-TLIF and open TLIF and was significant statistically. The hospital stay mean difference between both groups was statistically significant (2.88 and 5.12 days respectively). Mean visual analog scale (VAS) scores for back and leg pain decreased, respectively, from 6.66 and 7.44 to 2.58 and 2.07 in short-term follow up and to 1.38 and 0.78 in long-term follow up in group I and from 7.17 and 7.96 to 2.79 and 2.31 in short-term follow up and to 1.37 and 0.86 in long-term follow up in group II. Mean Oswestry disability index (ODI) improved from 54.07% to 27.82% in short-term follow up and to18.33% in long-term follow up in group I and from 60.5% to 2381% in short-term follow up and to 14.48 in long-term follow up in group II. In both groups, VAS and ODI scores significantly changed from pre- to postoperatively ( p < 0.001), but postoperative outcome between groups was statistically not significant. Regarding the operative complications, there was no nerve root injury in both groups. The incidence of dural tear was 3.5% in group I and 11.11% in group II. The incidence of superficial and deep infections, respectively, was (3.5% and 1.1%) in group I and (12.2% and 4.1%) in group II. There was no screw loosening or slipped cage in group I but screw loosening was reported in 2 cases (4.1%) and also cage slippage was reported in 2 cases(4.1%) in group II. Conclusion Clinical and functional outcomes demonstrate no significant differences between groups in treating back and leg pain of adult patients with spondylolisthesis. However, in terms of operative blood loss, dural tear, infection, hospital stay and instrument failure (screw or cage) mini-TLIF demonstrated better results. On the other hand, mini-TLIF showed more operatve time that can be overcomed with growing learning curve and advancing system designs.