Peruvian- my TB mare has DSLD. There is no way this disease is related to an injury. Dr. Kellen is a fraud- using her yahoo website to sell some herbs with little to no scientific backing and no controlled studies.
The University of Florida and the University of Georgia are both studying this disorder. I spoke to the pathologist at you of G and they believe the disease is systematic based on tissue samples. Injuries usually occur on one leg- not both or all 4 as is with this disease.
Another researcher is working on determining the genetic basis so they can test for it. So far they have narrowed it down, but they still have a long way to go.
These horses do not respond to stem cell treatment, shock wave therapy etc. Best guess is that it is similar to Ehlers danlos syndrome in people.
Sadly people are continuing to breed these horses. I saw a WB stallion the other day with an obvious case. It is even found in some very popular TB bloodlines as well (Mr. Prospector).
I highly suspect Mr. Prospector had the disease as his racing career was ended due to ankle problems, his pictures show dropped ankles on both hinds, and at least one of his offspring developed the disease as well.