What is the primary function of an Ankle Foot Orthosis (AAFO)?

The primary function of an Ankle Foot Orthosis (AFO) is to assist in limb clearance during the swing phase of gait. This is particularly important for individuals who exhibit foot drop or weakness in the dorsiflexors, which can lead to difficulty in lifting the foot clear of the ground when walking. By providing support and maintaining the foot in a properly dorsiflexed position during swing, the AFO aids in reducing the risk of dragging the toes and potential tripping, thus facilitating a smoother and safer gait pattern.

In contrast, while providing stability in stance through knee-ankle coupling is beneficial for certain conditions, the main objective of an AFO is not primarily oriented towards this function. Furthermore, controlling ankle position throughout stance is also a role of AFOs, but it is not the primary focus. Similarly, treating hypertonicity at the knee and ankle can be a secondary effect of using an AFO, but it is not the primary purpose. Thus, the role of an AFO in assisting with limb clearance during swing is paramount in its design and application, making it the key function for which it is utilized in clinical practice.