Fillauer has come up with an Orthotic Knee Extension Assist to facilitate immobilization in case of knee joint. This is a user friendly product as it is adjustable as par user convenience and can be affixed almost with any knee joint. The Extension Assist makes sure that the knee joint attains full extension and the lock engages in case of orthotic knee joints with a locking mechanism enabling patients in secure ambulation. The device is integrated with a mechanism that permits to let off after 35° of knee flexion which enable sitting without the continual pull of the mechanism, thereby reducing irritation and strain. The elastomeric tension is user adjustable which enable users to dial in the amount of assist according to their specific need for their own activities. This device is suitable for most of the knee joints. It, along with its extension force through a range of flexion angle degrees, ensures that knee joint reaches full extension. It aids in case of weak knee extensor musculature for better performance. The device ensures optimum function of knee joints.