Radiographic study of operative approach in minimally invasive oblique lumber interbody fusion

English Keywords:Minimally invasive oblique lumber interbody fusion  Radiography  Vessel  Psoas major

English Abstract:

  【Abstract】 Objectives: To analyze the relationship between the vessel and psoas major of L1/2-L4/5 levels, and to investigate the radiographic characteristics of the operative approach in minimally invasive oblique lumber interbody fusion. Methods: 113 cases were selected from the inpatients who had the lumbar MRI and anteroposterior(AP) lumbar film between November 2013 and September 2015. 12 cases were excluded due to the unclear imaging or other abdominal surgery history. Finally 101 cases were chosen, among whom there were 46 males and 55 females, aging from 51 to 68 years(average, 59.0±4.4 years). The distances between the vessel and psoas major of L1/2-L4/5 levels were measured on MRI, and the vertical distances between the upper end plate midpoint of L5 and left iliac crest were measured in the anteroposterior(AP) lumbar film. Results: The distances between the vessel and psoas major of L1/2-L4/5 levels were 20.7±5.63mm, 20.1±6.97mm, 19.5±6.20mm, 15.7±7.86mm respectively on the left side, and 15.3±6.29mm, 8.8±4.32mm, 7.1±4.34mm, 4.8±3.69mm respectively on the right side. The distance of left side at each level was significantly longer than that of right side(P<0.01), respectively. The distance decreased from level L1/2 to L4/5. The distance of L4/5 level was significantly shorter than that of other levels on left side(P<0.01), there were 9 subjects less than 5mm, and 2 of them had no gap between the vessel and psoas major. The vertical distances between the upper end plate midpoint of L5 and left iliac crest ranged from -33 to 19.6mm(average, -7.0±14.2mm), 30% of which had higher iliac crest than the upper end plate midpoint of L5. Conclusions: MRI is an effective way to access the operative approach in the minimally invasive oblique lumber interbody fusion preoperatively. There may be more benefit from the higher lever by using the minimally invasive oblique lumber interbody fusion. The distance between the left vessel and psoas major is longer than the right side, as a result, the left side is recommended as the surgical approach.