ORIGINAL ARTICLES
Reliability and Validity of Current Physical Examination
Techniques of the Foot and Ankle
James S. Wrobel, DPM, MS*
David G. Armstrong, DPM, PhD*
Background: This literature review was undertaken to evaluate the reliability and validity of the orthopedic, neurologic, and vascular examination of the foot and ankle.
Methods: We searched PubMed—the US National Library of Medicine’s database of
biomedical citations—and abstracts for relevant publications from 1966 to 2006. We
also searched the bibliographies of the retrieved articles. We identified 35 articles to review. For discussion purposes, we used reliability interpretation guidelines proposed by
others. For the κ statistic that calculates reliability for dichotomous (eg, yes or no) measures, reliability was defined as moderate (0.4–0.6), substantial (0.6–0.8), and outstanding (> 0.8). For the intraclass correlation coefficient that calculates reliability for continuous (eg, degrees of motion) measures, reliability was defined as good (> 0.75), moderate
(0.5–0.75), and poor (< 0.5).
Results: Intraclass correlations, based on the various examinations performed, varied
widely. The range was from 0.08 to 0.98, depending on the examination performed.
Concurrent and predictive validity ranged from poor to good.
Conclusions: Although hundreds of articles exist describing various methods of lowerextremity assessment, few rigorously assess the measurement properties. This information can be used both by the discerning clinician in the art of clinical examination and by
the scientist in the measurement properties of reproducibility and validity. (J Am Podiatr
Med Assoc 98(3): 197-206, 2008)
Foot problems are common, complex, and costly. Estimates from the National Health and Nutrition Examination Survey suggest that the prevalence of significant mobility problems in the United States affects
more than one in six adults.1 This figure increases to
nearly one in three for persons aged 60 years old or
older. Lower-extremity maladies play a central role in
these problems and have a substantial impact on
quality of life and self-efficacy.
Interest in the treatment of the lower extremity
has yielded a host of proposed measurements and
examination techniques designed to better quantify
the degree of pathology. However, there has been
comparatively little attention given to robust inquiry
into the reliability and validity of these techniques.
*Scholl’s Center for Lower Extremity Ambulatory Research, Rosalind Franklin University of Medicine and Science,
Chicago, IL.
Corresponding author: James S. Wrobel, DPM, MS, Center
for Lower Extremity Ambulatory Research, Rosalind Franklin
University of Medicine and Science, 3333 Green Bay Rd, North
Chicago, IL 60064. (E-mail: james.wrobel@rosalindfranklin.edu)
With this structured literature review we sought to
evaluate aspects of the orthopedic, neurologic, and
vascular examination of the foot and ankle.
Methods
We conducted a systematic literature search with
PubMed—the US National Library of Medicine’s online database of biomedical citations—and searched
abstracts available on the Internet. PubMed includes
16 million citations from more than 4,800 journals
published in the United States and more than 70
other countries, primarily since 1966. We searched
for foot exam and reliability, accuracy, or validity.
Criteria for inclusion included a well-described patient population and sampling technique. The examiner description and training had to be well described,
and the examination technique had to be described
well enough to be reproduced in a typical clinical setting. Additional inclusion criteria included valid statistical techniques and presentation of the data. With
these inclusion criteria, 27 studies were included
Journal of the American Podiatric Medical Association • Vol 98 • No 3 • May/June 2008
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from 133 potential studies for reliability, 19 studies
were included from 120 potential studies for accuracy, and for validity, 5 studies were included from 75
potential studies. The searching sequence (reliability
followed by accuracy followed by validity) affected
our yield because studies with more than one search
term were grouped under the first term searched and
found. Relevant references from the included studies’
bibliographies were also considered for inclusion. Of
the 51 included studies, findings from 38 studies are
reported here. Both authors had complete access to
the articles and met to agree for inclusion or exclusion of various studies.
Reliability can take on many forms depending on
the measure and its purpose. These include test-retest
reliability and interitem consistency from the psychometric literature. Test-retest reliability tests concepts
at different points in time when the underlying condition is not expected to change. Reliable items exhibit
similar scores over this period. Interitem consistency
tests the correlation of items within a conceptual domain to see if they agree with the overall concept.
From the clinical perspective, reliability is commonly
measured with intrarater reliability and interrater reliability form.
Validity from the clinical perspective is commonly
measured with predictive, criterion-related, and face
validity.2 Predictive validity successfully predicts an
outcome of interest. A prediction is sensitive if it detects differences important to the investigator. It is
specific if it represents only the characteristic of interest. Criterion validity agrees with other approaches. Face or content validity makes intuitive sense.2
For measures of reliability, many advocate avoiding
arbitrary cutoff points for the measures. For the purposes of our discussion, we used interpretation guidelines proposed by others so we could describe the current state of the foot examination measures. For the κ
statistic that calculates reliability for dichotomous
(eg, yes or no) measures, reliability was defined as
moderate (0.4–0.6), substantial (0.6–0.8), and outstanding (> 0.8).3 For the intraclass correlation coefficient that calculates reliability for continuous (eg, degrees of motion) measures, reliability was defined as
good (> 0.75), moderate (0.5–0.75), and poor (< 0.5).4
The SEM can roughly be interpreted as the number
by which examiners will tend to vary.
Results
The previously defined search criteria resulted in the
inclusion of 38 manuscripts described in Table 1. The
table divides the studies into the type of examination
performed, the number of examiners, the basic method
198
of examination, the reliability, and the investigators’
conclusions. Intraclass correlations on the basis of
the various examinations performed varied widely.
The range was from 0.08 to 0.98, depending on the examination performed.
Discussion
Orthopedic Examination
The orthopedic examination was the most studied
area of the clinical aspect representing 26 of 38 articles.5-25, 36-40 Visual estimation of the forefoot-to-rearfoot ratio may be more reliable than an estimate made
with a goniometer. In a study of ten patients,11 examiner experience with the two methods did not seem
to matter. The interrater reliability was poor with the
goniometer and good with visual estimation. Conversely, measuring first-ray mobility as normal, hypomobile, or hypermobile with qualitative methods (n =
60)9 showed poor interrater reliability, as did using a
ruler (n = 14)10 with a Glasoe device as the standard.
Range-of-motion testing appears to demonstrate
good reliability.5, 6, 8 In a study of 63 healthy Navy midshipmen, both active and passive range of ankle dorsiflexion was measured in the prone position. This
method revealed a good intrarater reliability and moderate inter-examiner reliability with mean absolute differences of 2° and 3°.5 These numbers compare favorably with a previous report, in which ankle dorsiflexion
was measured in the supine position.8
Elveru et al6 investigated the reliability of ankle
and subtalar joint motion for 50 patients of 14 physical therapists. They found ankle joint motion to have
good intrarater reliability; however, subtalar joint positions and neutral were found to have poor reliability.
Moderate interrater reliability was found with ankle
motion. The authors also stated that the therapists
had little or no experience in assessing a subtalar
joint.6
When first metatarsophalangeal joint motion was
measured in a weightbearing position, the average
error found was 12° and 16° in the dorsiflexed and
plantarflexed positions, respectively.7 This finding contradicts subsequent work that found good interrater reliability in first metatarsophalangeal joint dorsiflexion
measured in a weightbearing position.8 Different examination methods could partially explain the findings;
patients were asked to stand with one foot on the edge
of a stool7 and on the floor in a relaxed, bipedal stance.
This difference in technique may have added to the observed reliability differences.8
Manual muscle testing, including the supination resistance test, appears to demonstrate good reliability
May/June 2008 • Vol 98 • No 3 • Journal of the American Podiatric Medical Association
Table 1. Reliability and Validity of Lower-Extremity Examination Method by Examination Technique
Examination
Technique
Sample Size and
Examiner Type
Method
Reliability and
Validity
Author’s
Conclusion
Orthopedic Examination
Ankle dorsiflexion, leg
length discrepancy, medial talonavicular bulge,
rearfoot angle, arch
angle and foot type5
n = 63 Navy midshipmen; physical therapy
and athletic trainer
examiners
ICC = 0.65–0.97 with
88.8%–94.4% agreement
Results reliable when
conducted on healthy
individuals
Ankle and subtalar joint
motion6
n = 50; 15 physical therapist examiners
Intrarater ICC 0.74 for
ankle; Intertester ICC:
STJ inversion = 0.32,
STJ eversion = 0.17,
STJ neutral = 0.25, and
0.50 and 0.72 for ankle
With the exception of
ankle plantarflexion,
measures cannot be
considered reliable
First metatarsophalangeal joint mobility7
n = 20
Dorsiflexion and
plantarflexion
Average error = 12˚
(dorsiflexion) and 16˚
plantarflexion
Linear measurement
more accurate than
angular
Ankle and first metatarsophalangeal joint
mobility8
n = 10; two podiatrist
examiners
Supine ankle dorsiflexion and weightbearing
first metatarsophalangeal joint dorsiflexion
Interrater reliability was
0.71 for ankle and 0.95
for first metatarsophalangeal joint
Good reliability for ankle
and first metatarsophalangeal joint dorsiflexion
First-ray mobility9
n = 60; three clinician
examiners
Normal, hypomobility,
and hypermobility versus Glasoe device
Interrater κ statistic =
Poor agreement
0.143 for hypomobility
(30% agreement); 0.063
for normal (34% agreement); not calculated for
hypermobility (25%
agreement)
First-ray mobility 10
n = 14; three clinician
examiners
Ruler versus mechanical device
Device ICC = 0.98
(SEM = 0.15 mm)
Ruler intratest ICC =
–0.06 (SEM = 1.1 mm)
Ruler intertest ICC =
0.05 (SEM = 1.2 mm)
Poor reliability for ruler
method
Ball circumference7
n = 20
Average measurement
error = 1.1 cm
Linear measurement
more accurate than
angular
Forefoot-to-rearfoot
assessment11
n = 10; two physical
therapists and two
student examiners
Intrarater goniometer
ICC of 0.08 to 0.78
Intrarater visual ICC of
0.51 to 0.76
Interrater goniometer =
0.38
Interrater visual = 0.81
Visual estimation may
be more reliable
κ statistics very good
(0.61–1); however,
when normals excluded,
κ statistics were 0.55 to
0.88 (direct agreement,
11%–41%)
Reliability could be
improved with training.
Only use manual
muscle testing in
pathology if agreement
> 80%
Manual muscle testing12 n = 72, three examiners
Visual and goniometer
continued on next page
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Table 1. continued
Examination
Technique
Sample Size and
Examiner Type
Method
Reliability and
Validity
Author’s
Conclusion
Orthopedic Examination (continued)
Manual supination
resistance test13
n = 44; four clinician
examiners on 2 days
Test-retest reliability;
interrater ICC = 0.89,
intrarater ICC of 0.78 to
0.82, two inexperienced
clinicians’ ICC of 0.56 to
0.62 (poor)
Supination resistance
test may be clinically
useful in prescription
orthoses
Ankle laxity, stability,
and strength14
n = 21
Correlation (r ) > .75
High correlation
suggests reliability
Foot type15
n = 20
SAI, CSI, and NH to represent foot type by calcaneal alignment as
tested with footprint and
changes in alignment
over five test positions
SAI r = .5, CSI r =.6,
NH r = .8. Change in
degrees required to see
change in index score,
20 for SAI, 15 for CSI,
and 10 for NH
NH more sensitive to
change and thus had a
greater sensitivity to
changes in calcaneal
position
Medial arch16
n = 51
Five measures taken at
10% weightbearing and
90% weightbearing
Concurrent validity with
radiographs; dorsum
height at 50% of foot
length divided by
truncated foot length
(ICC = 0.81 for 10% and
0.85 for 90%)
The most reliable and
valid was arch height at
10% and 90% weightbearing, dividing dorsum height at 50% of
foot length by truncated
foot length
Resting calcaneal
stance position17
n = 88 adults;
n = 124 children
Adults = 6˚ everted
(SD = 2.71)
Children = 5.6˚ everted
(SD = 2.9)
Resting calcaneal
stance position was reliable; however, theoretical normal of 0 ± 2˚ not
observed
Limb-length
discrepancy18
n = 66 with 17
examiners
0.5-cm boards for
indirect measurement
with orthoradiograms
as standard
Concurrent validity; 81%
differed by 0–1.0 cm. No
differences amongst experience
Indirect limb-length
measurement accurate;
experience played no
role
Arch index, NH, FPI19
n = 95
Correlated with radiographs: NH, calcaneal
inclination angle, and
first metatarsalcalcaneal angle
Concurrent validity with
x-ray positions (pronated, neutral, and
supinated). NH r = .44,
.53, .79; arch index r =
.71, –.68, .52; FPI r =
.59, .36, .42
All methods provide
valuable information
about medial longitudinal arch; NH most
useful clinical measure
FPI20
n = 29 children;
n = 30 adolescents;
n = 30 adults
ICC children = 0.62,
adolescents = 0.74,
adults = 0.58; measurement error 1–1.5 points
on 33-point scale
Reliability moderate to
good
FPI21
n = 20
Four-phase validation
study of concurrent and
predictive validity; sixitem FPI predicted more
than 40% of variance
ankle joint complex
Stronger association
than most reports of
static and dynamic
measures
Derived measures from
119 papers; item reduction; six items compared
with static and dynamic
electromagnetic motiontracking system
continued on next page
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Table 1. continued
Examination
Technique
Sample Size and
Examiner Type
Method
Reliability and
Validity
Author’s
Conclusion
Orthopedic Examination (continued)
FPI22
Study 1: n = 31
Study 2: n = 12
Criterion validity of four
criteria for FPI with
radiographic criteria
as standard
Correlations poor
(–0.28 to 0.42); talonavicular angle significant;
significant changes from
supinated to resting
position and from
supinated to pronated
Criterion validity weaker
than expected although
significant correlation
and change with foot
manipulation for talar
head palpation
Observational gait
scale23
n = 20; two clinician
examiners
Knee and foot position
at mid-stance; base of
support and rearfoot
position with video
Intratest-weighted
κ statistic, 0.53–0.91
Intertest-weighted
κ statistic, 0.43–0.86
Base and rearfoot
ranges, 0.29–0.71
(intratest), 0.3–0.78
(intertest)
Angle and base of gait24
n = 25
Angle and base of gait
measured with footprints and clinical
tracings
ICC of 0.97–0.98 for
angle and 0.98–0.99 for
base of gait
Data similar; both are
useful clinical tools
One-legged stance25
n = 10
Rearfoot motion
STJ neutral, maximum
eversion, maximum
inversion
Concurrent validity with
electrogoniometer;
ICC of 0.76, 0.37, 0.39,
respectively; intratest
ICC of one-legged
stance = 0.92
Good interrater reliability for STJ neutral; rearfoot position one-legged
stance may be used to
approximate maximum
eversion during gait
Sensitivity, 80%;
specificity, 90%
Although small study,
toe response at time of
foot exposure frequently
provides evidence of
pyramidal tract
dysfunction
Disagreed in 18 of 145
fair intertester reliability
κ statistics = 0.73;
disagreement associated with age
Self-administered sensory tests allow patients
to participate in care but
should not replace
provider exam
Neurologic Examination
“Bedsheet” Babinski26
n = 20; 10 with neurologic disease and
10 without
Patient use of
monofilament27
n = 196
Nine centers, same-day
self-screen and clinician
examiner
Thermal sensitivity and
VPT28
n = 39
Babinski29
n = 10 (8 with upper
motor neuron lesion);
10 physician examiners
Toe response at the
time feet are exposed
Reliability coefficient for ICC of 0.89 (VPT)
thermal sensitivity and
and 0.54 (thermal
VPT
sensitivity)
Babinski κ statistic fair
(0.3); toe-tapping κ statistic substantial (0.73)
Babinski agreement =
56%; toe–tapping
agreement = 85%
Reproducible VPT is
inversely proportional to
age and better for men
Ability of Babinski sign
to identify upper motor
neuron lesion is limited.
Slowness of toe tapping
may be more useful sign
continued on next page
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Table 1. continued
Examination
Technique
Sample Size and
Examiner Type
Method
Reliability and
Validity
Author’s
Conclusion
Neurologic Examination (continued)
Monofilament, ankle
reflexes, pinprick,
vibration, position30
n = 304; ten centers of
internist and resident
examiners
Monofilament and ankle
reflex κ statistic moderate (0.59); pinprick,
vibration, and position
κ statistics fair
(0.28–0.36)
Conventional clinical
exam of diabetes mellitus feet had low reproducibility and correlated
poorly with monofilament. Monofilament was
reproducible, valid, and
the procedure of choice
Vascular Examination
Pedal pulse palpation31
n = 100
63% had systolic diastolic
pressure ≥ 118 mmHG;
68% had ABI > 0.82;
Predition ankle systolic
sensitivity (66%) and
specificity (91%)
Palpable pulse suggests ankle systolic
pressure ≥ 118 mmHG
and ABI > 0.82
Pedal pulse palpation32
n = 229
Test-retest reliability;
range of reproducibility
= 68%–81% for all four
pulses
Unacceptable variation
with monofilament the
best screening tool
Pedal pulse palpation33
n = 25; three vascular
surgeon and three
student examiners
κ statistics highest in
vascular techs (0.68,
good), vascular
surgeons (0.38, fair).
Best cutoff for ABI
between palpable and
nonpalpable = 0.76
underdiagnosed 30%
Pulses palpated under
unhurried conditions;
acceptable reproducibility and accuracy
ABI34
n = 246
ABI measured with
continuous-wave
Doppler versus
automated oscillometry
Concurrent validity with
standard ultrasound;
ankle systolic mean difference 2 mmHG
(± 6.7); 3.1 mmHG
(± 5.1 mmHG)
Both methods fell within
1% error and 5% reproducibility
ABI35
n = 201
ABI measured with
continuous-wave
Doppler versus automated oscillometry
Concurrent validity with
standard ultrasound;
correlation coefficient
0.78; mean difference
0.04 (± 0.01) and 0.06
(± 0.01)
Automated ABI reliable
Abbreviations: ICC, intraclass correlation coefficient; STJ, subtalar joint; SAI, Staheli arch index; CSI, Chippaux-Smirak
index; NH, navicular height; FPI, foot posture index; VPT, vibratory perception threshold; ABI, ankle-brachial index.
Note: Intertest refers to reliability among examiners on same patient. Intratest refers to reliability for the same examiner and
patient at different points in time.
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when used by experienced clinicians.12-14, 39 Ankle ligamentous laxity also appears to demonstrate good reliability.14 Relaxed calcaneal stance position appears to
demonstrate good reliability. In a study of 212 patients
with a two-arm goniometer and an electronic goniometer, the greatest mean difference within examiners
(intrarater) was 0.5°. Among examiners (interrater)
the greatest mean difference was 1.23° for the twoarm goniometer.17 Torburn et al25 further assessed the
reliability of rearfoot measures in ten patients. They
found that subtalar joint neutral position demonstrated
good reliability and that a relaxed, one-legged stance
was not significantly different from the observed
rearfoot eversion during gait.25
Other weightbearing measures demonstrated good
reliability.5, 9, 13, 14 These measures include angle and
base of gait, and limb-length discrepancy with a 0.5cm board. Observational gait analysis was studied in
14 patients with a three-point scale assessing rearfoot
motion and was found to have poor reliability.38 In a
subsequent observational gait scale study of 20 patients, investigators found acceptable reliability for
the foot position in mid-stance, initial foot contact,
and heel rise with weighted κ statistics ranging from
0.53 to 0.91 (intrarater) and 0.43 to 0.86 (interrater).23
The orthopedic examination is one of the most utilized in clinical podiatric practice. With the exception
of one study (Resch et al7), range-of-motion testing at
the ankle, subtalar joint, and first metatarsophalangeal joint seems to exhibit good to moderate intrarater reliability.5, 6, 8, 17, 25 The reliability of subtalar
joint range of motion testing may be enhanced with
additional training.6 Visual estimation of the forefootto-rearfoot relationship demonstrates good interrater
reliability over goniometer or stratifying first ray into
hypomobility, normal, or hypermobility.9, 11 Manual
muscle testing and ankle stability appear to demonstrate good interrater reliability.12-14, 39 Assessing limblength discrepancy with boards and some aspects of
visual gait analysis demonstrates good interrater reliability.5, 18, 23
Clinical measures for foot type and standing arch
postures are two of the most studied areas of the orthopedic examination.15, 16, 19-22, 37 In general, these have
been described in three categories: radiographic, anthropometric, and footprint measures.40 Mathieson et
al15 studied various footprint measures in 20 patients
positioned in five standardized positions. They investigated three foot type measures: the Staheli arch
index, the Chippaux-Smirak index, and navicular
height. The investigators examined the sensitivity of
the three foot type measures to detect alterations in
subtalar joint position as measured by calcaneal
frontal plane alignment.15 The Staheli arch index and
Chippaux-Smirak index demonstrated moderate reliability, and navicular height demonstrated good reliability. Change required to observe a change in index
score include 15° for Chippaux-Smirak index, 20° for
Staheli arch index, and 10° for navicular height. Navicular height was more sensitive to change and thus had
a greater sensitivity to changes in calcaneal position.
Mathieson et al15 concluded that foot type measures
derived from a static footprint exhibit limited responsiveness to changes in subtalar joint position.
Anthropometric measures of foot type are probably the most clinically useful. Arch height has received
much attention in the earlier literature. Williams and
McClay16 looked at five measurements of arch height
taken in two stance conditions, 10% and 90% weightbearing, in 51 patients. Reliability was good for dorsum height at 50% of foot length divided by truncated
foot length (intraclass correlation coefficient, 0.81 for
10% weightbearing and 0.85 for 90% weightbearing).
Dividing the dorsum height at 50% of foot length by
the truncated foot length was the most reliable and
valid of the five measures tested to clinically assess
arch height at the two stances.16 Menz and Munteanu19
performed a concurrent validity study on 95 patients
measuring navicular height, arch index, and foot posture index. They correlated these measures with radiographic angles of calcaneal inclination, calcaneal
first metatarsal declination, and navicular height.
They found that all three measures demonstrated significant correlations with the radiographic measures.
The authors concluded that the three measures provided useful, but different, information about arch
structure. Navicular height was believed to be most
clinically useful because of its higher concurrent validity and low technical difficulty.19
One of the most studied anthropometric measures
for foot type is the foot posture index.19-22 The original
description attributed to Redmond21 consisted of
eight criteria of talar head palpation, supralateral and
infralateral malleolar curvature, Helbing sign, calcaneal frontal plane position, prominent talonavicular
joint, congruence of the medial longitudinal arch, congruence of the lateral border of the foot, and abduction and adduction of the forefoot on the rearfoot.
Each criterion is graded on a five-point Likert scale
ranging from –2 to 2.20, Evans et al20 went on to study
inter- and intrarater reliability of the foot posture
index in children (n = 29), adolescents (n = 30), and
adults (n = 30) with four raters. Normalized navicular
height was the most reliable measure, except in children. Navicular drop, relaxed calcaneal stance position, and neutral calcaneal stance position demonstrated moderate to poor reliability. Forefoot-to-rearfoot
relationship was moderate to poor but improved as
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203
the patient group became older. The SEM was 2°,
which is high for the range of measures but favorable
compared with the other measures. None of the
measures exhibited adequate reliability in children.20
The foot posture index underwent further criterion validity testing with radiographic measures as the
standard in 31 patients.22 Correlations with radiographs were generally poor (–0.28 to 0.42), although
the talonavicular angle was significant. The responsiveness of the foot posture index was seen with significant changes from supinated to resting position
and from supinated to pronated position. The authors
concluded that criterion validity (with radiographic
measures) was weaker than expected, although significant correlation and change with foot manipulation for talar head palpation was observed.22
The foot posture index was also studied for criterion validity with static and dynamic data from an electromagnetic motion analysis system and was able to
predict 40% of the variance in dynamic ankle motion
with walking.21 The authors studied 91 patients in the
item-reduction phase, resulting in six of the eight original items being retained in the model (talar head palpation, supralateral and infralateral malleolar curvature,
calcaneal frontal plane position, prominent talonavicular joint, congruence of the medial longitudinal arch,
and abduction and adduction of the forefoot on the
rearfoot). Twelve patients were then analyzed for the
predictive validity phase with static and dynamic
weightbearing. The six-item foot posture index was
able to predict 40% of the variance in dynamic ankle
motion with walking.21 The amount of variance described is higher than previous reports that describe
static clinical measures predicting dynamic function.8
Foot type and standing arch postures appear to be
used more for research purposes, rather than clinical
care, and thus demand a higher level of reliability and
validity. Navicular height demonstrated good reliability
and more responsiveness to rearfoot change over the
Staheli arch index and the Chippaux-Smirak index.15
The most reliable and valid measure of arch height at
10% and 90% weightbearing stances was obtained by
dividing the dorsum height at 50% of foot length by
the truncated foot length.16
Neurologic Examination
Several studies have investigated the reliability of the
neurologic examination.12, 26-30, 39 Miller and Johnston29
observed ten patients and found the Babinski sign to
have fair interrater reliability for five neurologists and
five primary-care providers. Decreased speed of toe
tapping had better reliability and agreement for identifying patients with an upper motor neuron lesion.29
204
Berger and Fannin26 also studied 20 inpatients and
found the “bedsheet Babinski” had high sensitivity
and specificity for detecting patients with neurological disease. Brandsma et al12 studied 72 patients with
manual muscle testing. The interrater reliability was
substantial to excellent. However, when normals were
excluded, the interrater reliability was reduced to
moderate to substantial levels.12
Smieja et al30 studied the interrater reliability of
pinprick, vibration, deep tendon reflexes, position
sensation, and monofilament testing in 304 patients in
ten centers with internists and residents. They found
the monofilament and ankle reflex examinations to
have moderate reliability. The pinprick, vibration, and
position sense examinations had fair reliability.30 Birke
and Rolfsen27 studied the interrater reliability of the
monofilament examination on 196 patients at nine
centers and also found it to have substantial reliability.30 De Neeling et al28 studied the test-retest intrarater
reliability of thermal and vibratory perception threshold examination in 39 patients and found good reliability with thermal sensitivity demonstrating moderate
reliability. The neurologic examination demonstrated
good test-retest reliability for vibratory perception
threshold; moderate for thermal testing; and fair with
pinprick, vibratory, and joint position testing.28, 30 Monofilament and ankle reflex testing demonstrated moderate reliability.27, 30 For predictive validity of upper motor
neuron lesion, slowness of toe tapping had better interrater reliability and, along with the “bedsheet Babinski,” may predict disease better than the traditional
Babinski sign.26, 29
Vascular Examination
In the vascular examination, pedal pulse palpation
and ankle-brachial index were the most studied examinations for reliability.31-35 Lundin et al33 studied interrater reliability of pedal pulse palpation for vascular surgeons and students in 25 patients. They found
vascular technicians to have substantial reliability
and vascular surgeons to have fair reliability. The differences in results were attributed to hurried clinical
conditions. Klenerman et al32 also found substantial
test-retest intrarater reliability in pulse palpation in
229 patients studied. Raines et al34 (n = 246) and
Beckman et al35 (n = 201) studied automated oscillometry for calculating ankle-brachial indexes and
found the methods to be reliable. When looking at
pedal pulse palpation, it seems the best cutoff for
ankle-brachial index would range from 0.76 to 0.82.31, 33
These findings suggest there is a reservoir of peripheral arterial disease undetected by physical examination that might benefit from referral back to primary
May/June 2008 • Vol 98 • No 3 • Journal of the American Podiatric Medical Association
care should medical management not be optimal.41
Pedal pulse palpation demonstrated substantial reliability depending on clinician type and hurried clinical
conditions.32, 33, 42
We have attempted to describe the reliability and
validity of current foot examination. We understand
that the needs of the examination may differ on the
basis of application (clinical or research). Although
hundreds of articles describe various methods of
lower-extremity assessment, few have given rigorous
attention to these measurement properties. We hope
that future works in this area will include these critical measures to better guide the clinician in selecting
examinations that can accurately assess the functional and physiological status of the lower extremity.
The discerning clinician can then use this information
to strike the delicate balance between the art of clinical examination and the science of reproducibility
and validity.
Financial Disclosures: None reported.
Conflict of Interest: None reported.
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15.
16.
17.
18.
19.
20.
References
1. CENTERS FOR DISEASE CONTROL AND PREVENTION: Mobility
limitation among persons aged ≥40 years with and without diagnosed diabetes and lower extremity disease,
United States, 1999-2002. MMWR Morb Mortal Wkly Rep
54: 1183, 2005.
2. H ULLEY SB, C UMMINGS SR ( ED ): Designing Clinical Research, Williams & Wilkins, Baltimore, 1988.
3. L ANDIS JR, KOCH GG: The measurement of observer
agreement for categorical data. Biometrics 33: 159, 1977.
4. PORTNEY LG, WATKINS MP: “Statistical Measures of Reliability,” in Foundations of Clinical Research: Applications to Practice, ed by LG Portney and MP Watkins, p
505, Appleton and Lange, Norwalk, CT, 1993.
5. JONSON SR, GROSS MT: Intraexaminer reliability, interexaminer reliability, and mean values for nine lower extremity skeletal measures in healthy naval midshipmen.
J Orthop Sports Phys Ther 25: 253, 1997.
6. E LVERU RA, R OTHSTEIN JM, L AMB RL: Goniometric reliability in a clinical setting. Subtalar and ankle joint measurements. Phys Ther 68: 672, 1988.
7. R ESCH S, RYD L, S TENSTRÖM A, ET AL : Measuring hallux
valgus: a comparison of conventional radiography and
clinical parameters with regard to measurement accuracy. Foot Ankle Int 16: 267, 1995.
8. W ROBEL JS, C ONNOLLY JE, B EACH ML: Associations between static and functional measures of joint function
in the foot and ankle. JAPMA 94: 535, 2004.
9. C ORNWALL MW, F ISHCO WD, M C P OIL TG, ET AL : Reliability and validity of clinically assessing first-ray mobility
of the foot. JAPMA 94: 470, 2004.
10. GLASOE WM, GETSOIAN S, MYERS M, ET AL: Criterion-related
validity of a clinical measure of dorsal first ray mobility. J Orthop Sports Phys Ther 35: 589, 2005.
11. SOMERS DL, HANSON JA, KEDZIERSKI CM, ET AL: The influence of experience on the reliability of goniometric and
21.
22.
23.
24.
25.
26.
27.
28.
29.
30.
31.
visual measurement of forefoot position. J Orthop Sports
Phys Ther 25: 192, 1997.
BRANDSMA JW, VAN BRAKEL WH, ANDERSON AM, ET AL: Intertester reliability of manual muscle strength testing
in leprosy patients. Lepr Rev 69: 257, 1998.
NOAKES H PAYNE C: The reliability of the manual supination resistance test. JAPMA 93: 185, 2003.
B AUMHAUER JF, A LOSA DM, R ENSTRÖM AF, ET AL : Testretest reliability of ankle injury risk factors. Am J Sports
Med 23: 571, 1995.
MATHIESON I, UPTON D, PRIOR TD: Examining the validity
of selected measures of foot type: a preliminary study.
JAPMA 94: 275, 2004.
WILLIAMS DS, MCCLAY IS: Measurements used to characterize the foot and the medial longitudinal arch: reliability and validity. Phys Ther 80: 864, 2000.
SOBEL E, LEVITZ SJ, CASELLI MA, ET AL: Reevaluation of
the relaxed calcaneal stance position. Reliability and normal values in children and adults. JAPMA 89: 258, 1999.
PAKVIS DF, JAARSMA RL, VAN KAMPEN A: Limb-length measurements using wooden boards: an accurate and experienceindependent method [in Dutch]. Ned Tijdschr Geneeskd
147: 443, 2003.
MENZ HB, MUNTEANU SE: Validity of 3 clinical techniques
for the measurement of static foot posture in older people. J Orthop Sports Phys Ther 35: 479, 2005.
EVANS AM, COPPER AW, SCHARFBILLIG RW, ET AL: Reliability of the foot posture index and traditional measures
of foot position. JAPMA 93: 203, 2003.
REDMOND AC, CROSBIE J, OUVRIER RA: Development and
validation of a novel rating system for scoring standing
foot posture: the Foot Posture Index. Clin Biomech (Bristol, Avon) 21: 89, 2006.
SCHARFBILLIG R, EVANS AM, COPPER AW, ET AL: Criterion
validation of four criteria of the foot posture index.
JAPMA 94: 31, 2004.
MACKEY AH, LOBB GL, WALT SE, ET AL: Reliability and validity of the Observational Gait Scale in children with
spastic diplegia. Dev Med Child Neurol 45: 4, 2003.
C URRAN SA, U PTON D, L EARMONTH ID: Quantifying the
quasi-static angle and base of gait: a preliminary investigation comparing footprints and a clinical method.
JAPMA 96: 125, 2006.
T ORBURN L, P ERRY J, G RONLEY JK: Assessment of rearfoot motion: passive positioning, one-legged standing,
gait. Foot Ankle Int 19: 688, 1998.
B ERGER JR, FANNIN M: The “bedsheet” Babinski. South
Med J 95: 1178, 2002.
BIRKE JA, ROLFSEN RJ: Evaluation of a self-administered
sensory testing tool to identify patients at risk of diabetesrelated foot problems. Diabetes Care 21: 23, 1998.
DE N EELING JN, B EKS PJ, B ERTELSMANN FW, ET AL : Sensory thresholds in older adults: reproducibility and reference values. Muscle Nerve 17: 454, 1994.
M ILLER TM, J OHNSTON SC: Should the Babinski sign be
part of the routine neurologic examination? Neurology
65: 1165, 2005.
SMIEJA M, HUNT DL, EDELMAN D, ET AL: Clinical examination for the detection of protective sensation in the feet
of diabetic patients. International Cooperative Group for
Clinical Examination Research. J Gen Intern Med 14:
418, 1999.
KAZMERS A, KOSKI ME, G ROEHN H, ET AL: Assessment of
noninvasive lower extremity arterial testing versus pulse
Journal of the American Podiatric Medical Association • Vol 98 • No 3 • May/June 2008
205
exam. Am Surg 62: 315, 1996.
32. KLENERMAN L, MCCABE C, COGLEY D, ET AL: Screening for
patients at risk of diabetic foot ulceration in a general
diabetic outpatient clinic. Diabet Med 13: 561, 1996.
33. L UNDIN M, W IKSTEN JP, P ERÄKYLÄ T, ET AL : Distal pulse
palpation: is it reliable? World J Surg 23: 252, 1999.
34. RAINES JK, FARRAR J, NOICELY K: Ankle/Brachial index in
the primary care setting. Vasc Endovascular Surg 38:
131, 2004.
35. BECKMAN JA, HIGGINS CO, GERHARD-HERMAN M: Automated
oscillometric determination of the ankle-brachial index
provides accuracy necessary for office practice. Hypertension 47: 35, 2006.
36. B AKER CP, NEWSTEAD AH, MOSSBERG KA, ET AL: Reliability of static standing balance in nondisabled children:
comparison of two methods of measurement. Pediatr
Rehabil 2: 15, 1998.
206
37. MENZ HB: Alternative techniques for the clinical assessment of foot pronation. JAPMA 88: 119, 1998.
38. K EENAN AM, B ACH TM: Video assessment of rearfoot
movements during walking: a reliability study. Arch
Phys Med Rehabil 77: 651, 1996.
39. B ARR AE, D IAMOND BE, WADE CK, ET AL : Reliability of
testing measures in Duchenne or Becker muscular dystrophy. Arch Phys Med Rehabil 72: 315, 1991.
40. C OWAN DN, R OBINSON JR, J ONES BH, ET AL : Consistency
of visual assessments of arch height among clinicians.
Foot Ankle Int 15: 213, 1994.
41. AMERICAN DIABETES ASSOCIATION: Peripheral arterial disease
in people with diabetes. Diabetes Care 26: 3333, 2003.
42. EDELMAN D, SANDERS LJ, POGACH L: Reproducibility and
accuracy among primary care providers of a screening
examination for foot ulcer risk among diabetic patients.
Prev Med 27: 274, 1998.
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