Thanks for writing in.
Following a nasty fall, a large bruise
subsequently turning into a large bump in ?soft area of the thigh (muscles) is most likely to be a muscle injury
followed by hematoma
formation. Also you have mentioned it as hard and tender to touch.
If its been a while and its still tender (as you have told) then I suggest he consults an orthopedic surgeon who may get an ultrasound
of the region. Ultrasound scan will show any muscle injury or blood clot within the muscles.
An X ray
may also be indicated if your doctor feels it necessary after having examined the region.
If there is a small clot, it will resolve on its own. Should there be a larger clot a simple needle aspiration will treat the problem. He will also be given pain killers and antibiotics if required.
Hope this helps.