Question: In patients with plantar fasciitis, what is the short and
long-term effectiveness of foot orthoses?
Design: Randomized (allocation concealed), blinded (patients),
sham-controlled trial with 3 and 12-month follow-up.
Setting: A university podiatry clinic in Australia.
Patients: 136 patients who had a clinical diagnosis of plantar
fasciitis and had had symptoms for =4 weeks. Exclusion criteria were a
history of a major orthopaedic or medical condition that may have influenced
the development of plantar fasciitis. One patient dropped out before treatment
was given, leaving 135 patients (mean age, 48 y; 66% women). Follow-up was 99%
at 3 months and 97% at 12 months.
Intervention: Patients were allocated to customized foot orthoses (n
= 46), prefabricated foot orthoses (n = 44), or sham foot orthoses (n = 46).
The customized foot orthosis was made at a commercial orthotic laboratory. It
was made from semirigid polypropylene, was relatively rigid, provided
substantial support for the foot, and influenced the position of the foot in
relation to the leg. The prefabricated foot orthosis was a
three-quarter-length Formthotic (Foot Science International, Christ-church,
New Zealand), which was made from a firm-density polyethylene foam that filled
the arch area and prevented the orthosis from flattening. The sham orthosis
was made by molding 6-mm-thick, soft ethyl vinyl acetate foam over an
unmodified cast of the foot.
Main outcome measures: Pain and function at 3 and 12 months
(assessed with the Foot Health Status Questionnaire).
Main results: Analysis was by intention to treat. At 3 months,
patients who had prefabricated and customized orthoses had greater improved
function than those with the sham orthoses, but the difference was no longer
significant at 12 months
(Table). The differences for
pain were not significant
(Table).
Conclusion: In patients with plantar fasciitis, customized orthoses
or prefabricated orthoses improved function in the short term.
Plantar fasciitis and heel pain remain common complaints in foot and ankle
practice. Orthotic devices, a common treatment, may be over the counter
(immediately available and cheap), prefabricated (some fitting
required—medium cost), or customized (costly).
The study by Landorf and colleagues compared the benefit of prefabricated
and customized orthotic devices with that of sham treatment. Over-the-counter
orthotic devices were not studied. This is the first published study with
sufficient power to compare orthotic devices with sham treatment.
The authors did not outline how they confirmed that the patients had
plantar fasciitis, apart from stating patients were referred with the
diagnosis. Some patients may have been incorrectly diagnosed. The baseline
characteristics of the patients also differed: 1 group was, on the average, 10
kg heavier than the other 2, and the function score of the sham group was
higher than that of the other 2 groups. In addition, the assessor was not
blinded to the study groups, which may have caused bias. The treatments in
this study were not effective at 12 months. However, this may not be relevant
as plantar fasciitis is a self-resolving condition.
Physicians can feel confident referring patients for orthotic management
for short-term relief of plantar fasciitis. Customized orthotic devices had no
advantage over prefabricated ones. Both may have no advantage over the
immediately available and low-cost over-the-counter devices, but this was not
addressed in this study.