Topic: Foot Drop
Subject: Medicine
During the physical exam of a patients foot, you notice an inability to dorsiflex. What nerve root(s) is most likely affected?

Foot drop can be associated with a variety of conditions such as dorsiflexor injuries, peripheral nerve injuries, stroke, neuropathies, drug toxicities, or diabetes. Often drop foot is caused by injury to the common peroneal nerve (also called common fibular nerve, peroneal nerve, external popliteal nerve, lateral popliteal nerve), which is derived from the dorsal branches of the fourth and fifth lumbar and the first and second sacral nerves. The common peroneal nerve branches from the sciatic nerve. It includes the deep and superficial peroneal branches. These nerves provide sensation to the anterior and lateral parts of the legs and to the top of the feet. Symptoms of common peroneal nerve injury (foot drop) may include:
Inability to point toes toward the body (dorsiflexion)
Pain
Weakness
Numbness (on the shin or top of the foot)
Loss of function of foot
High-stepping walk (called steppage gait or footdrop gait)