Has he had x-rays done? If not then maybe would be a good idea to have them done.  I've not heard of this treatment being given for bruising, my vet would advise anti inflammatories and box rest for at least 3 weeks, so I'm not sure that the treatment you have had has worked or has had enough time to be effective.  Either way I would re consult the vet as limping is a definite indicator of pain.  An injury such as this can take a while to heal properly as well.