Injury to the common peroneal nerve is a recognized hazard of surgical procedures performed with the patients in certain positions. Pressure on the nerve as it wraps around the fibula, or stretch of the nerve, may produce transient or permanent neural damage, which is usually manifest as footdrop. In the present case bilateral footdrop and numbness of the feet occurred after a 14-hour craniotomy with the patient in the sitting position. This complication had not been previously reported as a complication of prolonged surgical procedures with the patient in the sitting position. It is hypothesized that the symptoms resulted from pressure on and stretch of the sciatic nerves.