There are numerous nerves in the foot and ankle and these can be injured by surgery, or indeed rarely by local anaesthetic blocks used to make the foot numb and control pain after an operation.
Nerve injury can cause symptoms of pain, numbness and weakness. Most muscles which move your foot receive their nerve supply higher up the leg so injury to nerves in the foot usually does not cause weakness. It can however cause numbness, tingling and pain. All three of these symptoms are common in the early stages after surgery when the foot tends to swell and most such early symptoms resolve with time.
​If nerve injury is going to recover, this can take up to two years. Ultimately if your symptoms do not recover you could be left with permanent numbness, tingling or have pain which requires treatment with painkilling drugs.