Adaptive Rocker Knife – Ergonomic Dining Aid for Weakened Grip, Arthritis & Dexterity Issues. Ideal Dining Aid: Perfect for users with weakened grip, arthritis, Parkinson’s, or dexterity issues. Thehigh-quality stainless-steel blade allows for smooth, effortless cutting using a gentlerocking motion, eliminating the need for sawing or excessive pressure.