Table 4 shows the factors patients perceived as important; most
commonly identified factors were comfort (98%), fit (90%), support
(90%), cost (60%), and weight (63%). Patients reported style (36%)
and color (33%) as being less important.
Factors influencing changes in foot characteristics and footwear.
Shoe width and depth did not correlate with foot pain, impairment,
and disability (data not shown). However, patients with poor
footwear reported higher foot-related impairment and activities,
particularly in the scores of the LSISAP (P = 0.01) and the FFI
impairment domain (P = 0.02) (Table 5). Secondary analysis
demonstrated no significant differences in any of the footwear
characteristics between participants with diabetes mellitus (n = 7)
and those without diabetes mellitus (n = 43; P > 0.05).
DISCUSSION
The aim of this study was to identify current footwear styles,
footwear characteristics, and factors that influence footwear choice
experienced by patients with chronic gout. Overall, we found severe
impairment and limited activity scores, consistent with significant
foot disability and impairment associated with gout. A previous
study has reported similar findings of foot pain, impairment, and
disability relating to chronic gout (7).
More than 40% of patients in the current study wore sandals,
moccasins, and flip-flops. A previous study (22) reported that gait
changes were observed in an asymptomatic population wearing
flip-flops and suggested that the shoe construction may contribute
to lower extremity leg pain and is counterproductive to alleviating
pain. The wearing of open-type footwear should be interpreted
with caution in the current study. It is important to understand that
open-type footwear, such as flip-flops and sandals, are commonly
worn in New Zealand. However, wearing open-type footwear
may reflect the issue of finding appropriate footwear, in particular
relating to finding footwear that has adequate foot width and length.
Analysis of patient footwear illustrated signs of detrimental changes.
Minimal motion control was found in the current study and since
the midfoot is required to form a rigid lever during propulsion,
footwear instability may contribute to foot problems in patients with
chronic gout. The current study found more than 50% of shoes
with a flexion point distal to the level of the first MTP joint. This
may limit gait efficiency due to altered kinematics that result from
inhibition of normal first MTP joint function (8). We can postulate
that a flexion point proximal may jeopardize the shoe’s stability and
may exacerbate the problem of efficient toe-off observed in patients
with chronic gout (7).
Heel height greater than 2.5 cm has been associated with hallux
valgus, plantar callus, and postural instability in older adults
(8). In our study, more than 40% of those with high heel height
wore athletic shoes. Athletic shoes vary significantly with midsole
construction that may use elements of gel, foamed polyurethane, or
air chambers that serve to aid cushioning (20). The elevated heel
height of athletic shoes may go some way to explain the high heel
height observed in this study.
The lack of cushioning found in shoes demonstrates the inadequate
amount of structural support for the foot and lower extremity.
Wear patterns on the footwear provided some indication that
they were partially worn, and there were considerable amounts
of medial compression signs. The poor midfoot sole stability and
poor heel counter stiffness found suggest that the current footwear
does not stabilize the foot during walking. The definition of poor
shoes (sandals, slippers, and flip-flops) used in this study implies
a shoe design with poor fit, poor foot posture, and a lack of shock
absorption characteristics. The lack of shock attenuation has the
potential to increase loads on plantar tissues, potentially leading to
foot pain. Combined with the presence of a flatfoot type, patients
with gout wear footwear that gives no support or cushioning and
is prone to unstableness. Therefore, footwear that has inadequate
stability, poor cushioning, and limited stability may exacerbate foot
pain in patients with gout.
Table 5. Differences between shoe fit category
and foot characteristics
Poor shoe
category,
mean ± SD Good shoe
category,
mean ± SD P
Leeds Foot Impact
Scale (impairment) 9.9 ± 6.5 6.5 ± 4.5 0.05
Leeds Foot Impact
Scale (activities) 17.2 ± 11.3 8.2 ± 8.7 0.01
Foot
Function Index
(pain) 43.5 ± 33.7 27.4 ± 22.4 0.07
Foot
Function
Index
(impairment) 45.9 ± 29.2 24.2 ± 26.4 0.02
Foot
Function Index
(limitation) 24.3 25.3 24.1 26.4 0.20
In the current study, the participants reported that fit and
comfort were important factors in choosing footwear, suggesting
that patients with gout may prioritize these factors due to their
condition. More than one-half of the patients reported cost as
a factor contributing to their footwear choice. The wearing of
poor shoes may be due to financial restrictions when purchasing
footwear. Furthermore, gout is a painful and distressing condition
that can have a major impact on economically active adults who
may be forced to give up work either temporarily or permanently
due to their condition (23,24). These data highlight the barriers
related to costs that patients with gout may encounter when
purchasing footwear.
We found no relationship between foot length and width and
Current Pedorthics
March/April 2013
27