How do doctors determine a level of foot drop? when you are sitting? standing?

Not sure about level: I am not sure about the level of foot drop, but the way i evaluated foot drop is by having pt walk and see how if the foot drags or slaps on the floor. I hope i got the question right. Low profile spring braces are available on the market that really help patients with foot drop. If you see a podiatrist, they can help you with that.

Walking: At least to me. As i wantto know the effect while ambulating....If the foot slaps on the floor if the patient can ambulate without falling etc...

Foot Drop: Observing you walk (gait) and manual muscle testing to determine your strength.

Are with previos: Answers only to add your doctor may order a nerve conduction study.