Background:

Minimally invasive surgical techniques have resulted in improved patient outcomes. One drawback is the increased reliance on fluoroscopy and subsequent exposure to ionizing radiation. We have previously shown the efficacy of a novel instrument tracking system in cadaveric and preliminary clinical studies for commonplace orthopedic and spine procedures. This study aims to examine the radiation and operative time using a novel instrument tracking system as compared to standard C-arm fluoroscopy in patients undergoing minimally invasive lumbar fusion.

Methods:

Radiation emitted, number of x-rays taken, and time to complete two tasks were recorded between instrument tracking and conventional C-arm fluoroscopy. Studied tasks included placement of the initial dilator through Kambin’s triangle during percutaneous lumbar interbody fusion (percLIF) and placement of pedicle screws during both percLIF and minimally invasive transforaminal lumbar interbody fusion (MIS-TLIF) with or without instrument tracking.

Results:

Twenty-three patients were included in the analysis encompassing 31 total levels. For the task of placing the initial dilator into Kambin’s triangle, an average of 4.21 minutes (2.4 vs. 6.6 minutes, p=0.002), 15 fluoroscopic images (5.4 vs. 20.5, p=0.002) and 8.14 mGy (3.3 vs. 11.4, p=0.011) were saved by instrument tracking. For pedicle screw insertion, an average of 5.69 minutes (3.97 vs. 9.67, p<0.001), 14 x-rays (6.53 vs. 20.62, p<0.001) and 7.89 mGy (2.98 vs. 10.87, p<0.001) were saved per screw.

Conclusions:

Instrument tracking, when utilized for minimally invasive lumbar fusion, leads to significant reductions in radiation and operative time compared to conventional fluoroscopy.