Foot drop is a gait abnormality leads to dropping of the forefoot happens due to weakness, irritation or damage to the common fibular nerve along with the sciatic nerve, or paralysis of the muscles in the anterior part of the lower leg.
Foot drop is characterized by the steppage gait. While walking, people suffering the condition drag their toes along the ground or bend their knees to lift their foot higher than usual to avoid the dragging. This serves to raise the foot high enough to prevent the toe from dragging and prevents the slapping.
Foot drop is the result of neurological disorder; only rarely is the muscle diseased or nonfunctional. The source for the neurological impairment can be central or peripheral. Foot drop occurs rarely because of a pathology involving the muscles or bones that make up the lower leg.
A foot drop of particular concern to orthopedic surgeons is the peroneal nerve palsy seen after total knee arthroplasty (TKA; 0.3-4% of cases) or proximal tibial osteotomy (3-13% of cases). Ischemia, mechanical irritation, traction, crush injury, and laceration can cause intraoperative injury to the peroneal nerve.