Let me recommend a simple technique that has done wonders with similar pains. Place a met-pad or met-bar millimeters behind the metatarsals heads. This will allow two things as full weight bearing is placed on the metarsals. First it will displaced weight bearing forces as the foot splays; second weight bearing forces will be diminished at area of pain allowing faster healing process. MAKE sure what you do in one foot you do on the other. DO NOT place only one met pad or met bar in only one foot....unless you want the patient to come back with other orthopedic problems this will cause.
regards