21/04/2026
The Össur OP4 Knee is a mechanical, pneumatic knee joint designed for above-knee prostheses. It offers:
Smooth, natural walking with adjustable swing phase resistance
Reliable stance stability through a weight-activated brake
High flexion (up to 145°) for easier sitting, stairs, and daily movements
Lightweight, durable design for energy-efficient mobility
Ideal for moderately active users (K2–K3) seeking safety and confidence
Whether it’s walking, climbing, or moving through daily life, the OP4 Knee helps users step forward with confidence and ease.