One leg seems to be twitching after surgery, which may be caused by anesthesia reaction, lack of calcium or cold legs. 1. reaction to anesthesia: during surgery, anesthesia drugs usually need to be injected, and the metabolism of anesthesia drugs in the body takes some time after surgery, which may affect the function of nerve tissues in the legs and cause twitching of the legs, and the abnormal symptoms will slowly improve after rest and observation. 2. Calcium deficiency: Surgery patients with calcium deficiency may also experience twitching in one leg after surgery, and need to actively replenish calcium in order to gradually reduce the twitching symptoms. 3. Cold legs: Due to the low temperature in the operating room, the legs may get cold after the operation, which may lead to muscle spasms in the legs and cause twitching, so you need to pay attention to keep warm in time, and you can cover the quilt for active observation. If you have a twitching leg after surgery, it is important to identify the cause of the twitching in time and take the correct treatment, and if necessary, you need to consult a doctor.