Study: Custom Orthotics Not Necessarily Better Than Prefab
Many podiatrists report positive benefits anecdotally of using custom orthotics to treat plantar fasciitis. However, a recent study published in the Journal of the American Podiatric Association (JAPMA) points out flaws in the current literature on the subject and suggests there is no current evidence basis to support the notion of custom orthotics being more effective than prefabricated orthotics for plantar fasciitis.
While authors of the study concede that the “vast majority” of articles in the last 30 years say orthoses are “highly effective” in reducing plantar fasciitis symptoms, they cite a “lack of scientific evidence … to fully inform clinical practice” on using orthotics for plantar fasciitis.
While patients in previous studies reported symptom relief, authors of the JAPMA study say earlier studies are flawed due to:
• a lack of using other treatments as controls for comparison;
• patient satisfaction measures that may have been more reflective of quality service than treatment outcomes; and
• the possibility of symptom resolution being due to limiting certain activities.
While they believe foot orthoses do have a role in managing plantar fasciitis, the authors of the study say the lack of sufficient evidence prevents any kind of determination on whether customized orthoses are more effective than prefabricated devices. They emphasize the need for more randomized controlled trials on this subject.
Assessing The Value Of The Study
Paul Scherer, DPM, disagrees with the authors’ assertion that only randomized controlled trials, and not outcome studies, can demonstrate effectiveness. He is not aware of an outcome study only for prefab orthotics. However, Dr. Scherer does agree with the study’s lead author Karl B. Landorf, DipAppSc (Pod), that several of the studies mentioned on this subject are “flawed in either the methods or statistical methods.”
He cites an article by Pfeffer, et. al., which attempts to compare functional orthoses with stretching and pads. According to Dr. Scherer, the study used several inexperienced technicians who viewed a instructional videotape on casting prior to casting for the custom orthoses.
“This is comparable to several different chemists making COX-2 inhibitors for the first time to evaluate the effectiveness of the drug,” argues Dr. Scherer, Chairman of the Department of Applied Biomechanics at the California School of Podiatric Medicine at Samuel Merritt College.
Douglas Richie Jr., DPM, agrees that the profession needs more randomized, controlled trials to determine the efficacy of custom versus prefabricated orthoses in treating plantar fasciitis. He says the JAPMA article “does an excellent job” critiquing the existing research and enumerating the “many shortcomings” of published studies.
“The current article points out there is simply not enough published evidence demonstrating the superiority of custom orthoses over prefabs,” asserts Dr. Richie, the President of the American Academy of Podiatric Sports Medicine. “This is not to say that custom orthoses are not superior, only that they have not been tested adequately according to acceptable scientific methodology.”
Emphasizing The Strengths And Appropriate Use Of Custom Orthoses
Several leading DPMs cite the advantages of custom orthotics.
“The authors’ assertion that a custom device is not more effective than a prefab device is difficult to understand,” says Eric Feit, DPM, a Fellow of the American College of Foot and Ankle Surgeons. “Custom orthotics are often the primary reason a patient is able to avoid surgery for plantar fasciitis.”
Dr. Scherer says custom orthotics are the most effective treatment for proximal plantar fasciitis. Citing an outcome study he published in JAPMA in 1991, Dr. Scherer says a functional device, when properly cast and fabricated, is 89 percent effective in producing more than 80 percent relief from the condition.
Dr. Feit notes a custom device is always superior to a prefab device in its fit, comfort and degree of clinical correction. Custom orthotics are advantageous in treating plantar fasciitis as they relax or support the fascia with weightbearing, which minimizes tension on the calcaneal insertion and allows micro-tears to heal, according to Dr. Feit.