In a KAFO, what structural part can cause excessive knee flexion if incorrectly positioned?

In a knee-ankle-foot orthosis (KAFO), the mechanical ankle joint plays a crucial role in controlling the position of the knee during ambulation. If the ankle joint is positioned incorrectly, it can lead to excessive knee flexion. The mechanical ankle joint acts as a pivot point and its alignment affects how forces are transmitted through the orthotic device.

If the ankle joint is set in a position that allows the foot to plantarflex too much, this can create an anterior pull through tendon action on the knee joint. This pull may cause the knee to flex more than desired, destabilizing the individual's gait and potentially leading to falls or a compromised stance phase. Proper alignment of the ankle joint is essential to maintain appropriate knee extension and support during walking.

Other structural components, like cuff height, calf section depth, and thigh section length, primarily influence the fit and alignment for overall stability and comfort but do not directly control knee flexion in the same manner as the mechanical ankle joint. Thus, misalignment or improper design of the ankle joint will have a more significant and direct impact on knee flexion than other parts of the KAFO.