PPD means permanent partial disability rating. It is a rating issued by your treating doctor (usually) and it is based on the AMA's Guides to the Evaluation of Permanent Impairment, 5th Edition. The Guides has been written for and by doctors. It is based on loss of range of motion permanently. The Guides is about 500 pages and is used all over the USA.
If you are at your maximum medical improvement point, your doctor should automatically give you a percentage impairment rating.
The insurer must begin payments of the rating within 14 days after the rating is published.
But no payment needs to be made if you are still receiving TTD or TPD benefits. Only one benefit can be paid to you at a time. There are a few exceptions, though.
A rating of 15% to your elbow for a fracture and surgical repair, if you have lost serious motion permanently, and if you are receiving $675 per week in benefits, could pay you $22,781.25.
A rating to your spine of 10%, due to loss of motion but without surgical intervention and if you are drawing $675 per week in benefits, could net you $20,250.
The insurer has the option of paying this benefit to you weekly and not in a lump sum.