Hello Teltotal,
Welcome to the pain management forum of MedHelp. I am glad that you found us. As our parents get older we deal with many of the problems that their aging brings.
Causes of leg pain include: muscle cramps, dehydration or depletion of potassium, sodium, calcium, or magnesium, injuries, inflammation, nerve damage, poor circulation and other conditions. Sometimes as we age pain and swelling in the lower extremities is frequently caused by decreased blood supply to the extremities. Swelling can go hand in hand with this but can also have other cardiac (heart) causes.
Your father is in need of a thorough medical work up. Doppler exams of his lower extremities can reveal the proficiency of his circulation. His physician may want to conduct exams to determine how well his heart is functioning. Today 70 is not considered old by the medical community. Admittedly it is not young but it is no longer viewed in this country as a greatly advanced age.
Your father is lucky to have a concerned child. Encourage him to get a good medical exam. Good luck to you and your father. Please feel free to let us know how he is doing or to ask additional questions.
Peace, Tuck
Does your Dad have any other health issues? It would help in trying to find the cause of his pain.