National Physical Therapy Examination (NPTE) Practice Exam

What is the most likely contributing factor for knee hyperextension during stance phase in a patient with a history of ankle sprains?

1. Soleus contracture retracting the tibia

2. Contralateral ABD weakness causing a trunk lean

3. Quads contracture pulling the knee in hyperextension

4. Degenerative joint changes causing a change in GRF

The correct answer is: Soleus contracture retracting the tibia

The most likely contributing factor for knee hyperextension during the stance phase in a patient with a history of ankle sprains is related to the effects of a soleus contracture on the tibia. The soleus muscle plays a crucial role in controlling plantarflexion and stabilizing the ankle joint during weight-bearing activities. When there is a soleus contracture, it can limit the ability to efficiently control the position of the tibia relative to the foot, especially during stance. This lack of control can lead to compensatory mechanisms that result in an excessive forward tilt of the tibia during the stance phase, which can push the knee into hyperextension. Hyperextension occurs as the body attempts to compensate for the lack of mobility and stability in the ankle joint resulting from previous sprains. Hence, the interplay between the soleus muscle's function and the position of the tibia is critical in understanding how such a contracture could predispose a patient to knee hyperextension. In contrast, while weakness in the contralateral hip abductors can influence trunk lean and overall gait mechanics, it is unlikely to be the direct cause of knee hyperextension. Similarly, a quadriceps contracture might impact knee positioning, but it is not a common factor leading to hyper