[
research report
]
Benjamin S. Boyd, PT, DPTSc1 • Linda Wanek, PT, PhD2
Andrew T. Gray, MD, PhD3 • Kimberly S. Topp, PT, PhD4
Mechanosensitivity of the Lower
Extremity Nervous System During
Straight-Leg Raise Neurodynamic
Testing in Healthy Individuals
C
linical neurological examinations are an integral part of
clinical decision making for determining neural involvement
in individuals with altered physical function and activity
participation. One aspect of a standard neurological
examination involves assessing the sensitivity of peripheral nerves to
limb movement, termed mechanosensitivity. Mechanosensitivity is
thought to be a normal protective mechanism that allows the nerves to
t Study Design: Cross-sectional, observational
study.
t Objectives: To explore how ankle position
affects lower extremity neurodynamic testing.
t BACKGROUND: Upper extremity limb move-
ments that increase neural loading create a protective muscle action of the upper trapezius, resulting
in shoulder girdle elevation during neurodynamic
testing. A similar mechanism has been suggested
in the lower extremities.
t Methods: Twenty healthy subjects without
low back pain participated in this study. Hip flexion
angle and surface electromyographic measures
were taken and compared at the onset of symptoms (P1) and at the point of maximally tolerated
symptoms (P2) during straight-leg raise tests
performed with ankle dorsiflexion (DF-SLR) and
plantar flexion (PF-SLR).
t RESULTS: Hip flexion was reduced during
DF-SLR by a mean  SD of 5.5°  6.6° at P1 (P =
.001) and 10.1°  9.7° at P2 (P.001), compared
to PF-SLR. DF-SLR induced distal muscle activation
and broader proximal muscle contractions at P1
compared to PF-SLR.
t Conclusion: These findings support the
hypothesis that addition of ankle dorsiflexion during straight-leg raise testing induces earlier distal
muscle activation and reduces hip flexion motion.
The straight-leg test, performed to the onset of
symptoms (P1) and with sensitizing maneuvers,
allows for identification of meaningful differences
in test outcomes and is an appropriate end point
for lower extremity neurodynamic testing. J
Orthop Sports Phys Ther 2009;39(11):780-790.
doi:10.2519/jospt.2009.3002
t Key words: neural provocation test, neural
tension, sciatic nerve, sensitizing maneuvers
respond to the mechanical stresses imposed upon them during movement.27
Neurodynamic tests are used to assess
the nervous system’s mechanosensitivity through monitoring the response to
movements that are known to alter the
mechanical stresses acting on the nervous system. The most common lower
quarter neurodynamic test is the passive
straight-leg raise (SLR) test.13,31 The basic
SLR test consists of the tester performing
passive hip flexion, with the patient in a
supine position and the knee held in full
extension.9
A recent systematic review of SLR
testing indicated a lack of standardization, including the use of various criteria
for determining the test end point.31 The
authors of this review reintroduced standardized methodology proposed by Breig
and Troup8 in 1979, including the use of
the first onset of pain as the end point
during the SLR test.31 Despite these recommendations, alternative end points,
such as maximally tolerated symptom,
are still utilized.17 Because SLR testing
is performed in both symptomatic and
Assistant Professor, Samuel Merritt University, Department of Physical Therapy, Oakland, CA; Visiting Assistant Professor, University of California, San Francisco, San Francisco, CA;
Visiting Assistant Professor, San Francisco State University, Graduate Program in Physical Therapy, San Francisco, CA. 2 Professor and Director of Physical Therapy, San Francisco
State University, Department of Physical Therapy, San Francisco, CA. 3 Associate Professor in residence at the University of California, San Francisco, Department of Anesthesia,
San Francisco General Hospital, CA. 4 Professor and Director of Physical Therapy, University of California, San Francisco, Graduate Program in Physical Therapy, San Francisco, CA;
Professor, Department of Anatomy, San Francisco, CA. This project was supported by NIH/NCRR UCSF-CTSI Grant Number UL1 RR024131. Its contents are solely the responsibility
of the authors and do not necessarily represent the official views of the NIH. Additional funding for this study was provided by a Graduate Student Research Award from the
University of California, San Francisco awarded to Benjamin Boyd and a Mary McMillan Doctoral Scholarship from the Foundation of Physical Therapy awarded to Benjamin Boyd.
The protocol of this study was approved by The Institutional Review Boards at University of California, San Francisco, San Francisco State University, and the Clinical Research Center
Advisory Committee at University of California, San Francisco. Address correspondence to Dr Benjamin S. Boyd, Assistant Professor, Department of Physical Therapy, Samuel Merritt
University, 450 30th Street, Oakland, CA 94609. E-mail: bboyd1@samuelmerritt.edu
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asymptomatic limbs, it is important to
know the normal healthy response of the
nervous system at both end points to support this recommendation.
Interpretations of neurodynamic examination findings are based primarily
on expert consensus.27 The proposed interpretations of a “positive” test include
considerations for whether the test (1)
reproduces the patient’s symptoms, (2)
identifies asymmetry between limbs or
significant deviation from norm, and (3)
induces changes in symptoms by distant
joint movement, also called “sensitizing
movements.”27 The third consideration
is critical to identify the nervous system
as the source of limitations to movement and is termed “structural differentiation.”32 Sensitizing movements involve
adding a limb movement distant to the
location of symptoms that would affect
the neural structures in the limb without
affecting the nonneural tissue local to the
area of symptoms.12
Ankle dorsiflexion is a common sensitizing maneuver for SLR testing.5,12,18
Studies in rats and dogs have demonstrated increased strain (elongation) in
the sciatic nerve at the proximal thigh
when ankle dorsiflexion was added to
SLR testing.1,7 Further support for the
use of ankle dorsiflexion as a sensitizing
maneuver is provided by findings from a
cadaveric study,12 in which prepositioning
the ankle in dorsiflexion created distal
movement in the tibial nerve at the knee
and ankle. Clinically, prepositioning the
ankle in dorsiflexion leads to a reduction
of hip range of motion during SLR testing, when taken to maximal resistance to
hip flexion in people with low back pain
and healthy individuals.5
Neurodynamic testing can also produce
increases in local muscle tone. SLR testing
without ankle dorsiflexion has been shown
to induce hamstring and gluteal muscle
activity when the hip flexion is held at
the maximally tolerated position.17 However, this study was performed on a small
number of subjects and statistical analysis
was not performed. In another study, an
increase in hamstring muscle activity was
shown at the maximum hip flexion range
(determined by the tester) in contrast to
relative electrical silence through the rest
of the range in healthy individuals.24 This
mean  SD increased activation was only
3%  1% of maximal voluntary contraction and was not a statistically significant
increase. Prepositioning in ankle dorsiflexion induces hamstring muscle activation earlier in hip flexion range during
SLR testing in healthy individuals.18 This
study also did not include statistical analysis. Muscle activity provoked during the
sensitized SLR test is thought to provide
a protective mechanism to restrict further
movement and to help prevent overstretch
nerve injuries.18 This is consistent with
findings in the upper limb, where passive
neurodynamic testing has been shown
to induce muscle activity from adjacent
musculature.2,11,14,36
No study to date has simultaneously
explored the differences in range of motion, symptoms, and muscle responses
for SLR neurodynamic testing at both
the onset and maximally tolerated symptoms in healthy individuals. In addition,
no study has provided statistical analysis of both proximal/distal and flexor/
extensor muscle activity during SLR
neurodynamic testing. It is important to
understand the specific effects of sensitizing maneuvers at each of these testing
end points in normal asymptomatic individuals to guide clinical decision making
and to help establish standardized testing methodology in symptomatic populations. The same test end point should
be utilized in the uninvolved and involved
limbs in people with nerve injuries, which
necessitates understanding the normal
response of the nervous system on the
uninvolved limb.
In this study we attempted to elucidate
the specific effects of the ankle dorsiflexion sensitizing maneuvers on the mechanosensitivity of lower extremity posterior
neural structures in healthy individuals.
The aims were to determine the amount
of hip motion and muscle activity during
2 versions of the SLR (including ankle
dorsiflexion sensitization) at 2 end-points
predefined as the onset of symptoms (P1)
and maximally tolerated symptoms (P2).
Additionally, we analyzed the reliability
of repeated SLR testing.
Methods
T
his cross-sectional study included 20 healthy participants
recruited from local medical and
academic communities. Exclusion criteria included low back or lower extremity
pain lasting longer than 3 consecutive
days in the past 6 months, peripheral
neuropathy, diabetes mellitus, complex
regional pain syndrome, lumbar spine
surgeries, chemical dependence or alcohol abuse, a history of lower extremity
nerve trauma, or chemotherapy in the
past year. Participants had to meet flexibility requirements of hip flexion of 90°
or more with the knee flexed, full knee extension, ankle dorsiflexion of 0° or more,
and plantar flexion of at least 30°. The
Institutional Review Boards at University
of California, San Francisco, San Francisco State University, and the Clinical
Research Center’s Advisory Committee
at University of California, San Francisco
approved this study. Written, informed
consent was obtained from the participants prior to testing. All participants
attended a single clinical assessment session. A subset of subjects (n = 5) returned
within 1 to 2 weeks for an identical clinical assessment session for reliability testing. One examiner (B.B.) performed all
physical examinations.
Clinical Assessment Session
Participants completed a medical history
questionnaire. In addition, the subjects
were instructed in the use of a visual
symptom-reporting card, which included
a body chart, an 11-point pain scale, and
a list of qualitative descriptors adapted
from the McGill Pain Questionnaire.25
The 11-point numeric pain rating scale
had the anchors of 0 (“no pain”) and 10
(“worst pain possible”). This type of scale
has good reliability and validity across
multiple ages and races.20,38
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Inc, Poland, OH) to maintain a fixed ankle position in either plantar flexion (30°)
or in neutral (0°) dorsiflexion. The SLR
performed with the ankle in 30° of plantar flexion (PF-SLR) was considered the
base or reference test, and the SLR performed with the ankle in neutral position
(DF-SLR) was considered the sensitized
SLR test (FIGURE 1A).
Electromyography (EMG) Setup
FIGURE 1. Neurodynamic testing set-up for the
straight-leg raise. (A) The subject's ankle was placed
in the adjustable ankle brace. (B) Electrogoniometers
were placed on the hip joint (EG1) and knee joint
(EG2). Surface electromyographic electrodes
(SEMGs) were placed over 8 right lower-extremity
muscles, including the biceps femoris, gluteus
maximus, medial gastrocnemius, rectus femoris,
semitendinosus, soleus, tibialis anterior, and vastus
medialis. A blood pressure cuff (BP cuff) was placed
under the lumbar spine. The subject was given a
custom-made joystick with a thumb switch that was
held with the subject's hands resting on the stomach.
The wall placard provided the tester with visual input
and was aligned with the axis in line with the subject's
right greater trochanter.
SLR Testing
The subject was positioned in supine,
with a 2.5-cm-thick foam head support
as the standardized position for neurodynamic SLR testing (FIGURE 1). Additional
pillows were provided if requested. A
blood pressure cuff bladder was centered
under the subject’s low back and was
inflated to 40 mmHg, just prior to SLR
testing. Changes in cuff pressure were
documented at end of movement, during SLR testing, as a gross assessment of
change in lumbar spine lordosis. Comparisons were made between the SLR
tests performed with the ankle in either
dorsiflexion or plantar flexion. The subject’s right ankle was placed in an APU
PRAFO ankle brace, with outrigger bar
and extra straps (Anatomical Concepts,
Standard 1-cm circular bipolar Ag/AgCl
surface EMG electrodes (Noraxon USA,
Inc, Scottsdale, AZ), with an interelectrode distance of 2 cm, were placed over
the gluteus maximus, semitendinosus, biceps femoris, medial gastrocnemius, soleus, rectus femoris, vastus medialis, and
tibialis anterior muscles of the right lower
extremity (FIGURE 1B). Electrode placement
was in accordance with surface EMG for
noninvasive assessment of muscles (SENIAM) guidelines.19 A single reference
electrode was placed over the right patella.
Skin preparation included cleaning and
vigorous rubbing with an alcohol-soaked
gauze pad. Three repetitions of 5-second
maximal voluntary isometric muscle contractions (MVC) were performed against
manually provided resistance, with the
subject in supine, for purposes of EMG
signal normalization.33,39 During MVC
testing, the limb was supported on pillows, if appropriate, and stabilized manually immediately proximal to the joint
being tested. Similar to other studies, the
calf musculature was tested in a neutral
ankle position, the quadriceps and hamstrings were tested with the knee in approximately 30° flexion, and the gluteal
musculature was tested in approximately
neutral hip flexion.33,39 MVC procedures
included instructions to either push or
pull against the examiner’s resistance and
to not let the examiner move the limb.
EMG signals were amplified (2000)
and acquired with a bandwidth frequency
of 50 to 500 Hz, and a sampling rate of
2000 Hz, using a TeleMyo 900 System,
NorBNC and A/D USB converter using
MRXP Master Package software, Version
1.06.21 (Noraxon USA, Inc).
]
Goniometer Setup
Twin-axis electrogoniometers (Noraxon
USA, Inc) were placed laterally across
the hip and knee joints to measure sagittal and coronal plane motion (FIGURE
1B).13,15,24,29 Coronal plane motions were
used to evaluate that neutral hip abduction and adduction were maintained
during testing. The hip goniometer was
placed with the proximal end parallel to
the subject’s torso adjacent to the iliac
crest and the distal end on the lateral
thigh, in line with the lateral femoral
condyle. The knee goniometer was placed
with the proximal end aligned with the
greater trochanter of the femur and the
distal end aligned with the lateral malleolus. Care was taken to ensure that the
middle of the goniometer coil was centered over the axis of rotation for each
joint. Goniometers were held in place
with double-sided tape and custommade neoprene straps (FIGURE 1B). A wall
placard provided the tester with visual
input of 10° increments and was placed
so that the origin was aligned with the
subject’s right greater trochanter. The
participants were given a custom-built
handheld electronic button (trigger),
which was held in the dominant hand
with both hands resting on the abdomen
(FIGURE 1B). Goniometer and trigger data
were acquired at 2000 Hz and synchronized with the EMG data, using the NorBNC and A/D USB converter (Noraxon
USA, Inc).
Testing Procedure
One instructional trial was performed
on the left lower extremity prior to formal testing of the right lower extremity.
For the right limb, a total of 4 SLR tests
were performed, with 2 trials assigned in
a random order for each ankle position.
The order was randomized to minimize
the effects of test order on the SLR outcomes. A metronome and wall placard
were used to facilitate consistent SLR
testing speed of approximately 5°/s (FIGURE 1B). The tester placed the subject’s
knee in full extension (defined as end
range resistance) without lifting the
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0.5 � 1.3
1.8
*
7.0
�
6.6
�2
Symptom Intensity
.1*
A
0.7 � 0.9*
2.5
P2
�
*
1.6
�
3.2
*
1.9
P1
0.1 � 0.3
Start
0.4 � 0.9
0.3 � 0.9
10.1 � 9.7*
24.
6*
57.
5�
Range of Motion
22.1
*
B
67.6
�
thigh off of the mat, and the subject was
instructed to indicate this start position
(“start”) by pressing the trigger 3 times.
While holding the knee in full extension,
the subject’s hip was moved passively
into hip flexion, while manually avoiding rotation, abduction, or adduction of
the femur. The subject indicated the onset of symptoms (P1) and the symptom
limit (P2) during the SLR by pressing the
handheld trigger. Specifically, the subject
was instructed to indicate “the moment
you feel the first onset of any symptoms”
(P1) and when “your symptoms become
too intense to continue and feel you cannot tolerate any further movement” (P2).
The motion was stopped at P2, and this
position was held for 5 seconds, before the
limb was returned to a resting position on
the plinth. Two-minute rests were given
between each SLR trial. Subjects were
asked to report symptom location, intensity, and quality at the start position, at
P1 (delayed reporting until immediately
after P2 because motion was not stopped
at this position), at P2, and then after a
2-minute rest.
1
�
0*
.6
9
15.
3
�
.1
34
P2
Data Processing
5.5 � 6.6*
*
3.7
P1
Surface EMG signals were converted
using a root-mean-squared (RMS) formula, with a 50-millisecond interval.
Mean voltage for EMG and degrees for
hip range of motion were obtained for
a 100-millisecond window centered on
each of the following 3 time points: start,
P1, and P2. For each muscle, MVC measurements were averaged from the center
3-second window of each of 3 repeated
MVC tests.33 SLR testing surface EMG
values were converted into percent MVC
for each muscle. A “triggered muscle
response” was defined as an increase in
EMG activity (expressed as percent MVC)
of at least a 1.5-fold above the supinelying, resting levels (taken lying supine
prior to establishing the start position).
For example, if there was 3.0% MVC
activity of the hamstring muscle in resting, the muscle was considered activated
(triggered muscle response) at 4.5% MVC
during SLR testing.
Start
FIGURE 2. Straight-leg raise neurodynamic test results are presented for (A) symptom intensity (0-to-10 scale) and
(B) hip flexion range of motion in degrees. Orange-lined body diagrams represent PF-SLR test and blue-lined body
diagrams represent DF-SLR test. Significance between tests is indicated by an asterisk (*) and was set at P.05.
Start represents the start position, P1 represents the first onset of symptoms, and P2 represents the maximally
tolerated symptoms. Data are mean  SD.
Goniometer Reliability Testing
The goniometers were attached to a rigid,
wood-hinged model to test the reliability
and validity of measurements compared
to fixed metal angles of 0°, 30°, 45°, 60°,
and 90°. Further reliability testing was
performed on a subset of 5 participants,
by performing 10 repeated SLR tests to
arbitrarily, but consistently, predetermined hip flexion positions. Specifically,
the beam from a laser level, placed on a
fixed wooden surface, was aimed horizontally across the room at an angle perpendicular to the subject’s limb and at
an arbitrary height within the subject’s
symptom-free hip flexion range of motion. A second tester pressed the trigger
when the subject’s limb blocked the laser
beam, and the hip flexion angle was then
measured.
Statistical Analysis
All statistical analyses were performed
using SPSS software, Version 14.0 (SPSS
Inc, Chicago, IL). Descriptive statistics
were used to describe the mean  SD for
all variables except frequency descriptive
statistics for symptom quality and loca-
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tion, which are reported as percentages.
Repeated-measures, general linear models were used for within-condition differences between the rest, start, P1, and P2
positions for EMG, range-of-motion, and
symptom intensity data. Between-test
comparisons (DF-SLR to PF-SLR) were
made using paired t tests. The general
linear model calculations were adjusted
due to nonsphericity using a GreenhouseGeisser correction. Pearson correlation
coefficients were calculated to assess the
relationship between the lumbar pressure cuff measure and hip flexion range
of motion at P2. An intraclass correlation
coefficient (ICC3,1) was used for repeatedmeasures reliability analysis and reported
with the 95% confidence interval (CI).
The minimal detectable change for hip
flexion range of motion was calculated
using the standard error of the measurement.23 Alpha was set at .05. Significance
was set at P.05.
Results
T
he average  SD age of the 20
participants was 50.4  12.0 years
(range, 25-63 years) and included
14 women and 6 men. Height was 1.7 
0.1 m, body mass was 71.2  24.8 kg, and
body mass index (BMI) was 25.9  8.8
kg/m2.
SLR Neurodynamic Testing
The average  SD for angular velocity of
the PF-SLR was 3.0°/s  1.0°/s and of the
DF-SLR was 2.8°/s  0.9°/s (P =.045).
Symptom Intensity
As expected, the mean  SD symptom
intensity at P1 and P2 was increased
above resting levels for both versions
of the SLR (P.001) (FIGURE 2A). There
was also an increased symptom intensity from P1 to P2 for both versions of the
SLR (P.001). During PF-SLR the mean
 SD symptom intensity went from 0.1
 0.3 at the start position to 2.5  1.6
at P1 and to 6.6  2.1 at P2. In contrast,
during DF-SLR, the mean intensity went
from 0.4  0.9 at the start position to
FIGURE 3. Sample surface electromyographic (EMG) recordings are presented. (A) Representative EMG activity
during DF-SLR for semitendinosis (SemT). Line represents the EMG signal normalized to the maximal voluntary
isometric contraction (MVC) and is reported as percent of maximal voluntary isometric muscle contractions
(percent MVC). Vertical lines demarcate the start position, the onset of symptoms (P1), and the maximally
tolerated position (P2). (B) Raw EMG signals for 1 subject comparing PF-SLR and DF-SLR with biceps femoris
(BicF), gluteus maximus (GluM), medial gastrocnemius (MedG), rectus femoris (RecF), semitendinosus (SemT),
soleus (Sol), tibialis anterior (TibA), and vastus medialis (VasM) muscles (top 8 lines) and hip flexion range of
motion (bottom line). Vertical lines demarcate the start position, the onset of symptoms (P1), and the maximally
tolerated position (P2).
3.2  1.9 at P1 and to 7.0  1.8 at P2.
The mean intensity at P1 was significantly higher by 0.7  0.9 points during
the DF-SLR compared to PF-SLR (P =
.002). There was no difference in mean
intensity between PF-SLR and DF-SLR
at the start position or at P2. In general,
symptom intensity was not correlated
with muscle activity (percent MVC), except at the start position. Muscle activity
(percent MVC) and symptom intensity
were significantly correlated at the start
position during the PF-SLR for the semitendinosus (r = 0.56, P = .013), anterior
tibialis (r = 0.53, P = .021), and vastus
medialis (r = 0.71, P = .001), and during DF-SLR for the semitendinosus (r =
0.49, P = .032). At P1 muscle activity was
significantly correlated with symptoms
during PF-SLR for the gluteus maximus
(r = 0.48, P = .039). There were no other
significant correlations between muscle
activity and symptom intensity at either
predefined point in either SLR test.
Goniometric Validity and
Reliability Testing
Repeated goniometric measures on the
wooden hinged model were a mean
 SD of 0.3°  0.2° for the known 0°
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TABLE
Muscle Activation Pattern*
PF-SLR
MuscleResting
DF-SLR
StartP1P2
StartP1P2
Soleus
6.8  2.8
9.0  6.0†
9.5  6.7†‡
11.8  9.6†
9.6  6.7†
11.1  9.1†‡
Medial gastrocnemius
5.2  1.5
6.4  3.0†
7.0  3.8†
8.2  5.7†
6.2  2.9†
7.4  4.1 †
8.7  5.5†
Tibialis anterior
2.7  1.1
3.1  1.4†‡
3.6  1.8†‡
4.1  3.4†‡
5.6  5.6†‡
5.6  4.4†‡
6.1  4.4†‡
Vastus medialis
7.2  4.1
9.1  7.3‡
12.0  13.7
17.0  16.7†‡
5.6  2.8†‡
12.3  13.7†
Rectus femoris
6.8  3.6
7.0  3.9
10.4  7.5†
10.9  8.2†
7.3  3.8
9.7  6.7†
10.7  6.9†
Semitendinosus
3.8  1.3
3.7  1.2
4.9  2.8
8.3  11.9
3.8  1.1
6.1  4.1†
10.0  11.4†
Biceps femoris
4.5  1.5
5.4  2.3†
6.3  3.9†
10.6  12.6†
5.3  2.6†
6.1  2.9†
9.6  11.5
12.1  4.5
15.4  10.5
16.3  10.1†
24.6  27.4†
15.4  10.4
16.9  12.0†
22.5  23.4
Gluteus maximus
12.7  10.6†
13.8  12.3†‡
Abbreviations: DF, dorsiflexion; MVC, maximal voluntary isometric muscle contraction; P1, onset of symptoms; P2, point of maximally tolerated symptoms;
PF, plantar flexion; SLR, straight-leg raise.
* Values are mean  SD percent MVC.
†
Statistically significant increase (P.05) above resting levels for general linear model of repeated measures for within-test differences.
‡
Statistically significant difference (P.05) between PF-SLR and DF-SLR tests, using paired t test comparison for start and P1 and P2.
angle, 31.3°  0.5° for the known 30°
angle, 47.8°  0.7° for the known 45°
angle, 64.1°  0.8° for the known 60°
angle, and 95.9°  1.3° for the known
90° angle. Reliability (ICC) of repeated goniometric measures in the sagittal and coronal plane on the wooden
hinged model was 1.00 (95% CI: 1.00,
1.00). Using a subset of 5 participants,
the range of variability with repeated
goniometric testing of hip flexion to arbitrary but consistent positions in the
symptom-free range (up to a maximum
of 40°) was from 1.0°  0.3° to 2.4° 
0.7°, with an ICC of 1.00 (95% CI: 0.99,
1.00). The minimal detectable change
for hip flexion range of motion was 0.4°
using this methodology.
Range of Motion
ICC3,1 for hip flexion range of motion
between trials were 0.87 (95% CI: 0.69,
0.95) for PF-SLR at P1, 0.96 (95% CI:
0.91, 0.99) for PF-SLR at P2, 0.78 (95%
CI: 0.50, 0.91) for DF-SLR at P1, and
0.88 (95% CI: 0.73, 0.95) for DF-SLR at
P2. The hip range of motion to P1 and to
P2 during the SLR test was greater than
the start position for both DF-SLR and
PF-SLR (P.001) (FIGURE 2B). In addition, hip range of motion was significantly greater at P2 than P1 for both PF-SLR
and DF-SLR (P.001). There was 13.9%
less hip flexion ROM at P1 during DFSLR compared to PF-SLR, with a 95% CI
from 2.4° to 8.6° (P = .001) (FIGURE 2B). At
P2 there was 14.9% less hip flexion ROM
in DF-SLR compared to PF-SLR, with
a 95% CI from 5.6° to 14.6° (P.001).
There was no difference in hip abduction/
adduction between PF-SLR and DF-SLR
at P1 (P = .318) or at P2 (P = .572). There
was no difference in knee flexion/extension between PF-SLR and DF-SLR at P1
(P = .124) or at P2 (P = .260). There was
no difference in knee coronal plane positioning between PF-SLR and DF-SLR at
P1 (P = .648) or at P2 (P = .498). Repeated
testing between multiple testing sessions
(mean  SD interval of 10.4  4.3 days)
performed on a subset of 5 subjects had
an ICC of 0.87 (95% CI: 0.68, 0.95) for
hip flexion ROM measurement.
Muscle Activation
The coefficient of variation for repeated
MVC trials was 14.23%, which supported
use of averaging of the 3 trials. There was
relative EMG silence of the muscles until muscle activation was triggered late
in the hip range of motion (FIGURE 3).
During PF-SLR, rectus femoris became
activated at P1 (P = .021) (TABLE). When
the PF-SLR was taken to P2, a slightly
different pattern of muscle activation was
seen. The rectus femoris remained acti-
vated (P = .025), while additional muscle
activation was seen in gluteus maximus
(P = .045), vastus medialis (P = .010),
soleus (P = .013), medial gastrocnemius
(P = .018), biceps femoris (P = .049), and
tibialis anterior (P = .037).
The addition of ankle dorsiflexion
created a different pattern of muscle activation (TABLE). During DF-SLR, muscle
activation criteria was met for the soleus
(P = .015), semitendinosus (P = .005),
tibialis anterior (P = .003), and vastus
medialis (P = .027) at P1. When taken to
P2 during DF-SLR, these 4 muscles remained activated (P = .010, P = .021, P =
.001, P = .014), and the medial gastrocnemius (P = .003) and rectus femoris (P =
.024) were triggered.
Between-test comparisons identified
a significantly greater soleus and tibialis
anterior muscle activation at P1 during
DF-SLR compared to PF-SLR (P = .042
and P = .008). At P2, there was a significantly higher activation of the tibialis
anterior and the vastus medialis during
DF-SLR compared to PF-SLR (P = .008
and P = .028).
Symptom Location
Eighty-five percent of the subjects had
no symptoms at the start position in PFSLR and 75% in DF-SLR (FIGURE 4). For
those subjects who reported symptoms in
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[
research report
Start
Ache
Ache
10%
Stretch
Stretch
Tightness/tension
Tightness/tension
Burning
Burning
Pain
Pain
Numbness
Numbness
10%
Tingling
Tingling
No symptoms
85%
No symptoms
75%
0 10 20 30 40 50 60 70 80 90 100
0 10 20 30 40 50 60 70 80 90 100
Percent (%)
Percent (%)
P1
Ache
Ache
15%
Stretch
Tightness/tension
10%
Stretch
75%
70%
Tightness/tension
25%
Burning
Burning
Pain
Pain
Numbness
Numbness
Tingling
Tingling
No symptoms
No symptoms
50%
15%
Percent (%)
Percent (%)
P2
Ache
Ache
15%
Stretch
Tightness/tension
75%
35%
15%
Stretch
65%
Tightness/tension
40%
Burning
Burning
Pain
Pain
Numbness
Numbness
Tingling
Tingling
No symptoms
No symptoms
0 10 20 30 40 50 60 70 80 90 100
0 10 20 30 40 50 60 70 80 90 100
Percent (%)
Percent (%)
PF-SLR
DF-SLR
FIGURE 4. Frequency of quality descriptors used to report symptoms during the PF-SLR and DF-SLR tests.
Histograms are presented for symptoms reported in at least 10% of the subjects at the start, onset of symptoms
(P1), and maximally tolerated position (P2), respectively.
the start position, the locations were the
right anterior leg, posterior hip, posterior
thigh, and posterior leg.
The frequencies of symptom locations
reported at P1 and P2 during SLR are
presented in FIGURE 5. During PF-SLR, the
most frequent symptom location for P1
was in the right posterior thigh, followed
by the right posterior leg. When this test
was taken to P2, the right posterior thigh
remained the most frequent symptom location, while the frequency of symptoms
in the right posterior leg increased. In
contrast, during DF-SLR, distal symptoms in the right posterior leg were more
(70% at P1 and 65% at P2), followed by
tight/tension (50% at P1 and 40% at P2),
and third most common was ache (10%
at P1 and 15% at P2). Pain and numbness
were reported infrequently during SLR,
and no subjects reported tingling or pins/
needles. After 2 minutes of rest following
the SLR test, 90% of the subjects reported no symptoms following PF-SLR and
70% reported no symptoms following
DF-SLR. The symptoms that remained
after PF-SLR were most commonly ache
(15%) and dull (10%), and after DF-SLR
were most commonly ache (15%) and
stretch (10%).
Lumbar Spine Pressure Cuff Measure
0 10 20 30 40 50 60 70 80 90 100
0 10 20 30 40 50 60 70 80 90 100
]
frequent at P1 and distal symptoms in the
right posterior leg and plantar foot were
more frequent at P2.
Symptom Quality
The frequencies of descriptors used by
the subjects to report symptom quality during both versions of the SLR are
presented in FIGURE 4. During PF-SLR,
the most common descriptor used was
stretch (75% at P1 and P2) and the next
most frequent was tight/tension (25%
at P1 and 35% at P2), followed by ache
(15% at P1 and P2). During DF-SLR, the
most frequent descriptor was also stretch
Repeated-measures reliability (ICC) of
the lumbar pressure cuff measurements
taken at P2 was 0.87 (95% CI: 0.69, 0.95)
for PF-SLR and 0.91 (95% CI: 0.78, 0.96)
for DF-SLR. Lumbar pressure cuff measurements increased from 40 mmHg at
start position to a mean  SD of 67.6 
11.5 mmHg at P2 during PF-SLR and
66.5  12.6 mmHg at P2 during DF-SLR.
The pressure in the cuff at P2 was not significantly different between PF-SLR and
DF-SLR (P = .298). Pearson correlations
between the lumbar pressure cuff measurement and hip flexion range of motion
at P2 were 0.77 (P.001) for the PF-SLR
and 0.79 (P.001) for the DF-SLR.
Discussion
T
his study further supports the
concept that ankle positions may be
used as sensitizing maneuvers to the
base SLR test. The quality and location
of symptoms were altered and a broader
muscular response was triggered with the
addition of the sensitizing maneuver of
ankle dorsiflexion. The higher symptom
intensity that we observed in healthy subjects at P1 during DF-SLR compared to
PF-SLR was statistically significant but
did not meet the 2-point threshold for
clinical significance and is therefore not a
meaningful difference.10 Hip flexion range
of motion was reduced during the dorsiflexion version of the SLR test at both the
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5%
5%
5%
80%
10%
35%
5%
91–100%
81–90%
15%
85%
20%
55%
10%
71–80%
61–70%
PF-SLR at P1
PF-SLR at P2
51–60%
41–50%
31–40%
21–30%
11–20%
1–10%
0%
5%
15%
10%
75%
5%
80%
60%
15%
80%
25%
5%
DF-SLR at P1
DF-SLR at P2
FIGURE 5. Body chart representations for frequencies of symptom location reported during the PF-SLR and DF-SLR
at the onset of symptoms (P1) and the maximally tolerated position (P2). Frequencies are reported in 10% intervals
from a white color of 0% frequency to 90% to 100% as dark red. There were more frequent distal symptoms in the
DF-SLR test when compared to the PF-SLR for both the P1 and the P2 time points.
onset and maximally tolerated symptoms.
The lower bound of the CI exceeded the
minimal detectable change, indicating
that this difference was a real difference
in range.28 Our results are consistent with
a previous study that identified a significant 9° reduction in hip range of motion
by the addition of ankle dorsiflexion.5
We hypothesize that the SLR with ankle
plantar flexion does not preload the sciatic, tibial, and plantar nerves, thus allowing the hip greater range of flexion before
the nerve complex undergoes sufficient
mechanical stress to trigger a symptomatic or motor response. Furthermore, we
hypothesize that the SLR with ankle dorsiflexion triggers an earlier restriction to
movement during SLR testing through
preloading of these neural structures.
This is supported by previous findings of
increased mechanical stress and strain on
the sciatic, tibial, and plantar nerves during ankle dorsiflexion.12
Changes in muscle tone were expected to be small during SLR testing, and
an appropriate threshold was necessary
to determine meaningful differences.
A previous study of an upper limb neural provocation test had documented a
statistically significant increase of approximately 1.5 times the muscle activity
compared to resting levels in upper trapezius muscle.2 We used this 50% increase
in muscle electrical activity over resting
muscle tone as a conservative threshold
to define “muscle activation.” This criterion was more stringent than previously
utilized thresholds of greater than 1, 2,
or 3 standard deviations above the resting mean electrical activity.22,33,34,36 In
fact, the criterion used in our study led
to a higher threshold for activation by an
average of 1.5% MVC compared to the
previously utilized methodology. It was
expected that stretch-induced increases
in muscle tone would be no greater than
25% MVC.2 This was indeed the case during the passive SLR test for all muscles
measured in this study.
As expected, progression of the end
point of the SLR from P1 to P2 triggered
EMG activity in more muscles than had
been activated at P1. In the PF-SLR,
moving to P2 triggered activity in gluteus
maximus, vastus medialis, biceps femoris, tibialis anterior, soleus, and gastrocnemius, in addition to the rectus femoris,
which was active at P1. Progression of the
SLR from P1 to P2 triggered cocontractions of antagonist muscle groups, as has
been documented in an upper limb neurodynamic test.36 Additionally, although
the intensity of symptoms increased from
P1 to P2, we did not observe a correlation
between the increase in symptom intensity and the increase in muscle activation.
This is in agreement with the work of
Balster and Jull2 in an upper limb neurodynamic test of healthy subjects. In contrast, van der Heide et al36 documented a
correlation between the onset of pain and
muscle activity in an upper limb neurodynamic test in healthy subjects. In this
latter study, however, the correlation was
determined using only the subjects who
experienced pain consistently. It is possible that progression of the SLR from
the first onset of symptoms to maximally
tolerated symptoms results in a global attempt to stop the movement by stabilizing
the joints with cocontractions, as hypothesized by van der Heide and colleagues36
in their study of the response of biceps
brachii, triceps brachii, and trapezius in
an upper limb neurodynamic test.
The addition of dorsiflexion to the
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[
base SLR induced muscle activation in
both the soleus and the tibialis anterior at P1. The distal muscle activation
was not seen at P1 in the PF-SLR. This
muscle response was not likely due to
volitional changes in muscle activation,
as the subjects were instructed to remain
relaxed throughout the SLR testing and
were masked from viewing the EMG
recordings. Distal muscle activity at the
first onset of symptoms in the DF-SLR
leads us to hypothesize that this is a protective reflexive mechanism of the local
muscle to stop further stress and strain
of the nerves by limiting further motion.
Such a local protective response has been
demonstrated in the upper limb, wherein neurodynamic tests that elongate the
brachial plexus result in increased surface EMG activity of the upper trapezius
muscle and increased contractile force of
muscles that elevate the shoulder.2,36 Our
study demonstrated that the mass muscle
activation pattern presents earlier in the
SLR if the limb is in ankle dorsiflexion.
As expected, during the SLR, symptoms
reported by healthy subjects differed from
those reported previously by people with
lower limb radicular pain.6 In our study,
a few subjects described minimal dull,
ache, sore, or tenderness in the posterior
hip, thigh, or leg at the start position, in
which the knee was moved into full extension. It is likely that elongation of the soft
tissue in the posterior limb provoked the
symptoms. During the SLR testing, the
most frequent symptoms reported were
stretch or tension in the posterior thigh
or leg. The addition of ankle dorsiflexion
to the base SLR provoked more tension,
tightness, and burning, and more distal
location of symptoms. In these healthy
subjects, pain and numbness were reported infrequently (10%). In contrast, SLR
testing in people with lower limb radicular
pain has been found to provoke reports of
“pain” in 83% of the symptomatic limbs
at a mean of only 58° of hip flexion.6 This
study also identified the frequent report of
deep symptoms that may follow a myotomal or sclerotomal pattern.6
Some researchers have proposed the
research report
first onset of pelvic movement as an end
point for SLR testing when used as a lower extremity flexibility assessment,16,21,30,37
but it is unclear if this is an appropriate
end point for SLR neurodynamic testing. One research study indicated that
pelvic movement occurred simultaneously with hip flexion during the SLR
test even when the pelvis was strapped to
the table.4 Another study found that pelvic motion began after the first 10° and
that lumbar lordosis began to decrease
after 30° of hip flexion motion during
the SLR.17 Our study suggests that, as hip
range of motion increases during SLR,
the pressure under the lumbar spine also
increases. We found excellent reliability
of this measurement during SLR testing
and a strong relationship between hip
range of motion and the amount of pressure measured under the low back at P2
(Pearson r = 0.77-0.79). Further research
is necessary to determine whether the
increase in pressure in the SLR is due to
movement of the lumbar spine and pelvis, or to changes in the muscle activity
of the erector spinae in the region of the
blood pressure cuff. Regardless of the
mechanism, it appears that movement of
the pelvis or lumbar spine would not be
an appropriate end point for the SLR test
when used as a neurodynamic test.
What end point should be used for stopping neurodynamic tests of asymptomatic limbs that allows for both sufficient
information gathering and protection of
the person being tested? Our study has
shown excellent reliability of hip flexion
measurements at the onset of symptoms
(P1) on the same day (ICC = 0.78-0.96)
and repeated testing in subsequent weeks
in subjects with healthy nervous systems
(ICC = 0.87). We found that the altered
ankle position of only 30° between the
PF-SLR and DF-SLR created differences in hip ROM, symptom intensity, and
muscle activation that were measurable
at P1. In our study, taking the test to the
maximally tolerated position (P2) did
not provide additional clinically relevant
information. For example, the muscle response was widespread and not specific to
]
ankle position, symptom intensity was not
discriminatory for ankle position, and P1
had already allowed for identifying reductions in range of hip flexion motion with
ankle dorsiflexion. Although testing to P2
had excellent repeatability, it carries with
it risks, such as overstretch and further irritation of the nervous system, particularly when used with people in pain or with
suspected nerve injuries.
One of the limitations to our study is
extrapolating this information to people
who have pain. Our findings are from
people with healthy nervous systems and
provide guidelines for expectations in the
asymptomatic limb of those patients with
pain down 1 lower extremity. The presence of pain or injury in the injured limb
may induce a different response in the
asymptomatic limb. Therefore, care
should be taken in extrapolating the outcomes from this study to individuals who
have pain, even when testing their asymptomatic limb. Future research should
consider the influence of neuropathic and
nonneuropathic pain on the outcome of
the SLR in the asymptomatic limb.
Limitations of application of our
findings to the clinical setting also include the precise measurement tools
and standardized protocols required to
determine small range-of-motion differences between PF-SLR and DF-SLR.
The equipment used in this study is not
readily available to the clinician, and the
procedures are too time consuming to be
feasible in patient care. It is possible that
clinicians can detect this 5° difference
in hip flexion range of motion between
PF-SLR and DF-SLR, as this is slightly
greater than the intraobserver variability
for standard hip goniometery of 3° and
inclinometry of 2.7°.3 It is possible that
hip rotation occurred during this SLR
testing, which could have influenced our
outcomes (we did not measure this axis
of motion in this study). Nevertheless,
standardized procedures and precision
measurements can be used clinically
to minimize the risks of confounding
variables such as poorly controlled limb
movement, different patient instructions,
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and different range-of-motion measurement tools. Clinically, full ankle dorsiflexion range of motion can be used during
SLR (compared to dorsiflexion to 0° used
in our study) to increase the impact of
sensitizing maneuvers by, theoretically,
increasing the stress to the posterior elements of the lower extremity nervous
system. In addition, a conceptual understanding of the impacts of sensitizing
maneuvers on symptoms, nerve mobility,
and muscle activity will assist with interpretation of SLR outcome measures. 35
There is a limitation in making definitive conclusions based on the variability
in the EMG data found in our study. Possible cross talk between muscles could
have influenced the EMG findings. Because not all subjects respond with the
same muscle activation pattern, extrapolation of our findings to clinical settings
could be unwarranted at this phase. A
better understanding of all of the possible
response patterns and why individuals
respond differently is necessary to ensure
that the assessment of muscle response
is not misinterpreted in a clinical setting.
Further exploration of muscle responses
in the lower extremity in various populations of people with pain during neurodynamic testing is warranted. Finally,
it is quite possible that structures other
than nerves and their associated connective tissue, such as blood vessels and fascia that span multiple joints in the limbs,
could be contributing to the alteration
in range of motion, muscle activity, and
symptoms that were found in this study.
Conclusion
M
echanosensitivity of the nervous system is a normal protective mechanism that includes
symptom production, increases in muscle
tone, and subsequent reductions in range
of motion in the lower limb during neurodynamic testing. Performing the SLR
to the first onset of symptoms is an assessment tool that is highly reliable in asymptomatic limbs of healthy individuals,
allowing for identification of meaningful
differences in test outcomes through the
use of sensitizing maneuvers, and may
be of use in patients with irritable conditions. Normal protective muscle guarding
induced by the nervous system to avoid
overstretch in healthy individuals should
be considered when assessing resistance
felt during SLR testing and considered
when prescribing muscle and soft tissue
stretches. t
Key points
FINDINGS: Ankle dorsiflexion, when used
as a sensitizing maneuver for SLR
neurodynamic testing, increases the
frequency of distal symptoms, triggers a
broader muscular response, and subsequently reduces the amount of hip flexion range of motion when tested to the
first onset of symptoms.
Implications: The use of ankle dorsiflexion is an appropriate sensitizing maneuver for SLR neurodynamic testing, and
performing the test to the first onset of
symptoms provides sufficient information to assist structural differentiation.
Caution: This study was limited to individuals with no history of nerve injury
and the use of precise instrumentation
for assessing range of motion and muscle activity. Caution should be exercised
in extrapolating these findings to clinical measurement tools and to populations with nerve injury.
Acknowledgements: The authors would like
to thank Isabel Belkind, Stephanie Boyd, Ryan
Broms, Nancy Byl, Sean Darling, Romy Havard, Adriane Kauffman, Alyssa Keeney-Roe,
Stephanie Klitgord, Andrew Moon, Michael
Ng, Steve Paul, Sandra Radtka, and Zheng
Xu for their assistance with data collection and
processing, and manuscript editing.
references
1. B
abbage CS, Coppieters MW, McGowan CM.
Strain and excursion of the sciatic nerve in the
dog: biomechanical considerations in the development of a clinical test for increased neural
mechanosensitivity. Vet J. 2007;174:330-336.
http://dx.doi.org/10.1016/j.tvjl.2006.07.005
2. B
alster SM, Jull GA. Upper trapezius muscle
activity during the brachial plexus tension test in
asymptomatic subjects. Man Ther. 1997;2:144149. http://dx.doi.org/10.1054/math.1997.0294
3. Bierma-Zeinstra SM, Bohnen AM, Ramlal R,
Ridderikhoff J, Verhaar JA, Prins A. Comparison
between two devices for measuring hip joint motions. Clin Rehabil. 1998;12:497-505.
4. Bohannon RW. Cinematographic analysis of the
passive straight-leg-raising test for hamstring
muscle length. Phys Ther. 1982;62:1269-1274.
5. Boland RA, Adams RD. Effects of ankle dorsiflexion on range and reliability of straight leg
raising. Aust J Physiother. 2000;46:191-200.
6. Bove GM, Zaheen A, Bajwa ZH. Subjective
nature of lower limb radicular pain. J Manipulative Physiol Ther. 2005;28:12-14. http://dx.doi.
org/10.1016/j.jmpt.2004.12.011
7. Boyd BS, Puttlitz C, Gan J, Topp KS. Strain and
excursion in the rat sciatic nerve during a modified straight leg raise are altered after traumatic
nerve injury. J Orthop Res. 2005;23:764-770.
http://dx.doi.org/10.1016/j.orthres.2004.11.008
8. Breig A, Troup JD. Biomechanical considerations
in the straight-leg-raising test. Cadaveric and
clinical studies of the effects of medial hip rotation. Spine. 1979;4:242-250.
9. Butler DS. The Sensitive Nervous System. Unley,
Australia: NoiGroup Publications; 2000.
10. Childs JD, Piva SR, Fritz JM. Responsiveness of
the numeric pain rating scale in patients with
low back pain. Spine. 2005;30:1331-1334.
11. Coppieters M, Stappaerts K, Janssens K, Jull
G. Reliability of detecting 'onset of pain' and
'submaximal pain' during neural provocation
testing of the upper quadrant. Physiother Res
Int. 2002;7:146-156.
12. Coppieters MW, Alshami AM, Babri AS, Souvlis
T, Kippers V, Hodges PW. Strain and excursion
of the sciatic, tibial, and plantar nerves during a
modified straight leg raising test. J Orthop Res.
2006;24:1883-1889. http://dx.doi.org/10.1002/
jor.20210
13. Coppieters MW, Kurz K, Mortensen TE, et al. The
impact of neurodynamic testing on the perception of experimentally induced muscle pain. Man
Ther. 2005;10:52-60. http://dx.doi.org/10.1016/j.
math.2004.07.007
14. Coppieters MW, Stappaerts KH, Wouters LL,
Janssens K. Aberrant protective force generation during neural provocation testing and the
effect of treatment in patients with neurogenic
cervicobrachial pain. J Manipulative Physiol
Ther. 2003;26:99-106.
15. Dingwell JB, Cusumano JP, Sternad D, Cavanagh
PR. Slower speeds in patients with diabetic neuropathy lead to improved local dynamic stability
of continuous overground walking. J Biomech.
2000;33:1269-1277.
16. Girouard CK, Hurley BF. Does strength training
inhibit gains in range of motion from flexibility
training in older adults? Med Sci Sports Exerc.
1995;27:1444-1449.
17. Goeken LN, Hof AL. Instrumental straight-leg
raising: a new approach to Lasegue's test. Arch
journal of orthopaedic & sports physical therapy | volume 39 | number 11 | november 2009 |
01 Boyd.indd 789
789
10/15/09 4:25:51 PM
[
Phys Med Rehabil. 1991;72:959-966.
18. Hall T, Zusman M, Elvey R. Adverse mechanical tension in the nervous system? Analysis of
straight leg raise. Man Ther. 1998;3:140-146.
19. Hermens HJ, Freriks B, Disselhorst-Klug C, Rau
G. Development of recommendations for SEMG
sensors and sensor placement procedures. J
Electromyogr Kinesiol. 2000;10:361-374.
20. Herr KA, Spratt K, Mobily PR, Richardson G.
Pain intensity assessment in older adults: use
of experimental pain to compare psychometric
properties and usability of selected pain scales
with younger adults. Clin J Pain. 2004;20:207219.
21. Hsieh CY, Walker JM, Gillis K. Straight-leg-raising
test. Comparison of three instruments. Phys
Ther. 1983;63:1429-1433.
22. Kautz SA, Patten C, Neptune RR. Does unilateral
pedaling activate a rhythmic locomotor pattern
in the nonpedaling leg in post-stroke hemiparesis? J Neurophysiol. 2006;95:3154-3163. http://
dx.doi.org/10.1152/jn.00951.2005
23. Kovacs FM, Abraira V, Royuela A, et al. Minimum
detectable and minimal clinically important
changes for pain in patients with nonspecific neck pain. BMC Musculoskelet Disord.
2008;9:43. http://dx.doi.org/10.1186/1471-24749-43
24. McHugh MP, Kremenic IJ, Fox MB, Gleim GW.
The role of mechanical and neural restraints
to joint range of motion during passive stretch.
Med Sci Sports Exerc. 1998;30:928-932.
25. Melzack R. The McGill pain questionnaire: from
description to measurement. Anesthesiology.
2005;103:199-202.
26. Moseley GL, Nicholas MK, Hodges PW. A ran-
research report
27.
28.
29.
30.
31.
32.
33.
domized controlled trial of intensive neurophysiology education in chronic low back pain. Clin J
Pain. 2004;20:324-330.
Nee RJ, Butler D. Management of peripheral
neuropathic pain: integrating neurobiology, neurodynamics, and clinical evidence. Phys Ther
Sport. 2006;7:36-49.
Noteboom JT, Allison SC, Cleland JA, Whitman
JM. A primer on selected aspects of evidencebased practice to questions of treatment. Part
2: interpreting results, application to clinical
practice, and self-evaluation. J Orthop Sports
Phys Ther. 2008;38:485-501. http://dx.doi.
org/10.2519/jospt.2008.2725
Pang MY, Yang JF. Sensory gating for the
initiation of the swing phase in different directions of human infant stepping. J Neurosci.
2002;22:5734-5740.
Raab DM, Agre JC, McAdam M, Smith EL. Light
resistance and stretching exercise in elderly
women: effect upon flexibility. Arch Phys Med
Rehabil. 1988;69:268-272.
Rebain R, Baxter GD, McDonough S. A systematic review of the passive straight leg raising
test as a diagnostic aid for low back pain (1989
to 2000). Spine (Phila Pa 1976). 2002;27:E388395.
Shacklock M. Improving application of neurodynamic (neural tension) testing and treatments:
a message to researchers and clinicians.
Man Ther. 2005;10:175-179. http://dx.doi.
org/10.1016/j.math.2005.03.001
Shultz SJ, Carcia CR, Perrin DH. Knee joint laxity
affects muscle activation patterns in the healthy
knee. J Electromyogr Kinesiol. 2004;14:475-483.
http://dx.doi.org/10.1016/j.jelekin.2003.11.001
]
34. S
hultz SJ, Perrin DH, Adams JM, Arnold BL,
Gansneder BM, Granata KP. Assessment of
neuromuscular response characteristics at the
knee following a functional perturbation. J Electromyogr Kinesiol. 2000;10:159-170.
35. Topp KS, Boyd BS. Structure and biomechanics of peripheral nerves: nerve responses to
physical stresses and implications for physical
therapist practice. Phys Ther. 2006;86:92-109.
36. van der Heide B, Allison GT, Zusman M. Pain
and muscular responses to a neural tissue
provocation test in the upper limb. Man Ther.
2001;6:154-162. http://dx.doi.org/10.1054/
math.2001.0406
37. Wang SS, Whitney SL, Burdett RG, Janosky
JE. Lower extremity muscular flexibility in long
distance runners. J Orthop Sports Phys Ther.
1993;17:102-107.
38. Ware LJ, Epps CD, Herr K, Packard A. Evaluation of the Revised Faces Pain Scale, Verbal
Descriptor Scale, Numeric Rating Scale, and
Iowa Pain Thermometer in older minority adults.
Pain Manag Nurs. 2006;7:117-125. http://dx.doi.
org/10.1016/j.pmn.2006.06.005
39. Worrell TW, Crisp E, Larosa C. Electromyographic reliability and analysis of selected lower
extremity muscles during lateral step-up conditions. J Athl Train. 1998;33:156-162.
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