Since you seem to be offline, ill leave a response here which we can discuss later on.
Now this sort of swelling following trauma can be very concerning especially if there is overlying bruising in the area. The first thing which comes to mind is that he could have damaged a vessel in the area which is bleeding and causing the swelling in the area. This would also cause bruising in the area and would be more likely if he was on blood thinning medication of any sort like warfarin or aspirin. If there is bruising then you should DEFINITELY contact urgent care and have this evaluated. This would be diagnosed on a clinical examination and maybe even a MRI.
Another cause of this can be associated with the lymphatic system of the leg. It is possible that there may be damage to the lymph vessels. If this is the case then there could be swelling which may be diagnosed on the basis of a clinical examination And in most cases this would be treated with compression stockings etc.
Now the most concerning possibility is that he could have developed a clot in the leg. This is a distinct possibility after injuries of this sort. If this is the case then he would have swelling, raised temperature over the area and sometimes even pain. The diagnosis would have to be made with the help of an immediate doppler USG and then treated with blood thinning medications.
There is a possibility that this is only fluid retention and not any of the other conditions which i mentioned, but considering the risk of a blood clot i would STRONGLY recommend that you have this evaluated at urgent care with atleast a doppler ultrasound of the leg. If this is a clot then early treatment is recommended.
Do you have any more questions?
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