Is 2D Fluoroscopy Reliable in Minimal Invasive Spine Surgery? Evaluation of Perforation Indices in MIS-TLIF

Abstract

Objective The aim of this study is to assess reliability of 2D Fluoroscopy in Minimal Invasive Surgery Transforaminal Lumbar Interbody Fusion (MIS-TLIF) through evaluation of perforation indices in 1,200 percutaneous pedicle screw instrumentation. Methods It is a single center retrospective study of 300 consecutive patients undergoing single level minimal invasive lumbar interbody fusion surgery (MIS-TLIF) under 2D Fluoroscopy. Percutaneous pedicle screws were analyzed with post-operative CT scan to assess accuracy of pedicle screw placement, Grades of perforation, Critical vs. Non critical Nature, Location of violation. Neurological implications of misplaced screws, Demographic, Clinical Parameters, outcome scores viz. Visual Analogue Score (VAS), Oswestry Disability Index (ODI) were also assessed. Results Overall rate of screw perforation was 5% (60/1,200) with different grades of perforation(Medial=24, Lateral=30, Inferior=1, Superior=5, Anterior=0) (Grade 1=42, Grade 2=18, Grade 3=0). Critical perforations were noted in 18 patient but none of the patients with critical and non critical perforation developed any neurological complications or post-operative leg pain. Conclusion This study showed overall pedicle perforation rate of 5% (60/1,200) in lower lumbar single level MIS-TLIF for grade 1 degenerative spondylolisthesis including grade 1 perforations are 3.5% and grade 2 perforation are 1.5%. 2D Fluoroscopy guided percutaneous pedicle screws placement with appropriate technique in MIS-TLIF is an acceptable and reliable procedure with low rates of screw related complications and revisions.

Keywords

• critical perforations
• degenerative lumbar disease
• minimally invasive surgery(mis)
• pedicle screws
• transforaminal lumbar interbody fusion