Evaluation of the FrameLock reference-arc fixation device for image-guided surgery.

Abstract

The FrameLock (FL) is a bone anchored, reference arc fixation device for image guided surgery. This study compares the stability of the FL to the FESS frame (FF), a friction fit device. The FL and FF were independently applied to a cadaver. Fifteen sequentially larger impulse forces were applied to each device (0.39-5.8 N*s). Following each impulse, anatomic drift was recorded. A 29 patient prospective clinical trial tested the accuracy of each device before and after surgery. The FL showed significantly less anatomic drift for all weights except 0.39 N*s ( P < 0.01). The average clinical displacement of the FL was 0.07 mm, and of the FF was 1.02 mm ( P < 0.0009). Linear regression analysis of anatomic drift as a function of the procedure duration revealed a positive correlation for the FF (y = 0.61x), but not for the FL (y = 0.02x). Conclusions The bone anchored FL is significantly more stable than the friction fit FF.