Lateral wedges - a crossover study
OUTCOME MEASUREMENT
Outcome assessments were conducted by the
same blinded assessor. Testing sessions at the
University included completion of self-report
questionnaires and objective assessment of
physical function.
Self-reported knee and foot symptoms were
the clinical outcomes of interest. Participants
completed the Western Ontario and McMaster
Universities Arthritis Index (WOMAC) Likert
version, from which the pain and physical
function subscales were calculated [26]. The
WOMAC contains 24 items that quantify pain (5
items), stiffness (2 items), and physical function
(17 items) that has been used in numerous knee
OA studies. Foot symptoms were assessed using
the Foot Function Index (revised - short form)
(FFI-R). This self-report questionnaire consists
of 34 items that provide the ability to quantify
aspects of foot pain, disability and activity
limitation [27]. For the purposes of this study,
the pain and stiffness subscales were used. Each
question is rated from 1 (no pain or stiffness)
to 4 (severe pain or stiffness). Given that “not
applicable” is a potential response for some
questions, questions rated as “not applicable”
were removed and the remaining scores within
that subscale were summed. Subscale scores
were then converted to a percentage of the
maximum potential score for that particular
subscale with 25% indicating no pain or
stiffness and 100% indicating severe pain or
stiffness.
Objective physical function was assessed using
the timed stair climb test, where participants
were instructed to ascend 12 stairs “as quickly
as possible” and the fastest time from two
attempts was recorded [28]. Adherence to each
insole intervention was self-reported in daily log
books. Participants reported the total number
of hours of shoe wear each day as well as the
total number of hours wearing the insole. Wear
time was then calculated by the research team
following the intervention, and expressed as
total number of insole wear hours, as well as a
percentage of total shoe wear time. Participants
also recorded perceived adverse effects of the
insoles, and changes in treatment regimens
FIGURE 1: Intervention insoles. Left: the lateral
wedge only condition consisted of a sulcus-
length 5-degree lateral wedge. Right: the lateral
wedge plus custom foot arch support involved
the 5-degree sulcus length lateral wedge built
into a negative of the volumetric cast that
provided the support across the entire foot.
Current Pedorthics | January/February 2019
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