Paralytic equinus during the swing phase is often caused by injury to which nerve?

Paralytic equinus during the swing phase typically results from dysfunction in the muscles responsible for dorsiflexion of the foot, which are primarily innervated by the common peroneal nerve. When this nerve is injured, the ability to lift the foot during the swing phase is compromised, leading to an inability to achieve neutral ankle positioning. This results in the foot remaining in a plantarflexed position, commonly referred to as equinus deformity.

The common peroneal nerve is crucial for controlling the tibialis anterior muscle, which plays a significant role in dorsiflexing the foot and preventing dragging of the toes during ambulation. The impact of the paralysis can lead to a characteristic gait disturbance, where the affected individual compensates for the lack of dorsiflexion, highlighting the importance of the nerve in maintaining proper gait mechanics.

Other nerves such as the femoral nerve, tibial nerve, and sciatic nerve serve different functions and primarily affect other muscle groups or movements—such as hip extension and knee flexion—rather than directly influencing the dorsiflexion necessary to prevent equinus during the swing phase. Thus, the common peroneal nerve is the correct focus when diagnosing and understanding the implications of paralytic equinus in