What is a potential cause for excessive knee flexion during initial contact in transtibial prostheses?

Excessive knee flexion during initial contact in transtibial prostheses can indeed be attributed to a faulty suspension system. The suspension system is critical for maintaining the alignment and stability of the prosthesis on the residual limb. If the suspension is not secure or functioning properly, it can lead to an improper fit or alignment, which may cause the knee to flex excessively during weight-bearing activities, such as initial contact when the foot strikes the ground.

Proper suspension is necessary for effective load transfer and control, directly impacting the user's gait mechanics. When there is insufficient suspension, the prosthetic socket may shift, leading to altered biomechanics and increased knee flexion.

In contrast, while foot alignment issues, inadequate socket fit, and improper limb length can contribute to gait problems, they are not as directly linked to excessive knee flexion during initial contact as a faulty suspension. For example, a misaligned foot primarily affects the stability and positioning of the foot rather than the direct mechanics of the knee joint during the initial contact phase.