Good summary: Shippert, et al (2009):
Current Orthopaedic Practice: April 2009 - Volume 20 - Issue 2 - p 130–135 doi: 10.1097/BCO.0b013e318199da68
SPECIAL FOCUS: Foot and Ankle - Recent updates in the management of plantar fasciitis
Schippert, David W; DiGiovanni, Benedict F; Baumhauer, Judith F; Flemister, Adolph S