At approx. 9:20 AM, EE was installing a side shift slide on FL177. While reattaching the carriage to the mast, it slipped and fell, pinching R index finger between the backrest and mast. EE sustained a fractured n lacerated finger, requiring sutures, x-ray, splint, and medication. Able to work-restricted from using (r) hand at work but later changed to limited use of (r) hand.