This is actually a very common phenomenon. After the fracture, the patient must stay in bed, the affected limb is raised, the affected limb does not fall to the ground, and there is no load. The muscles of the affected limb will be disused (reversible) to varying degrees. When you can go to the ground, due to the effect of gravity and the decline of the "muscle pump" function of atrophic muscles, the blood return of lower limbs slows down and the blood stagnates, so the affected limb will swell again. The function of muscle pump means that with walking, exercise and other actions, muscle contraction and relaxation will squeeze venous blood vessels and promote blood return. So, don't worry.