Hi Australia Calling,
I had the same symtom in the arch with just a small pea sized nodule for the past 8 years. I also wear orthodics. Unfortunately a cord developed and this year I had RT. which resulted in the nodule disappearing and the cord reduced by 50 %. I suggest you monitor the nodule , marking the base of the foot with a marker pen and take a photograph noting the date keeping it for a record. I was treated by Prof. Seegenschmiedt, who is a runner and he made a suggestion that I try the Nike Free shoes .(I know we are not supposed to give a free plug )The base of the shoe is segmented and maker advertises that it is like runnung bare feet. I 've given them a go and found they are very comfortable. Try using a creme which contains Urea.
Keep an eye on the back of your hands for knuckle pads. I would wait a watch at this stage.
Regards.

Australia Calling. Hi:
As all this is a bit new to you ,I would read some of the articles on the Dupuytrens Society web pages http://www.dupuytren-online.info Morbus Dups /Ledderhose & Peyronies Disease have many similarities.
Read the articles on' Ledderhose' and click onto 'Dupuytren disease' -open the literature window. On the 5th para. there is an article written by" Luck". Pages 641/642 give some understanding about cords. When a cord developed, through my left arch, it became painful and difficult to walk bare feet .(Even walking on the beach sand was very difficult.) That has all changed since RT. I also wear orthodics as I have high arches . The orthodics do spread the load over the arch area. I am now trying for short times not to use them.
The cream containing urea puts moisture back into the skin and the massage to the base of the foot doesn't do any harm. The creme contains 10% urea ,however I found "Scholl" in Germany have a 25% creme. I used this after RT. for dry skin, and the other thing its not greasy . Regards.

Edited at 07/11/08 10:29