hall2016

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Accepted Manuscript
Title: Validity of clinical outcome measures to evaluate ankle
range of motion during the weight-bearing lunge test.
Author: Emily A. Hall Carrie L. Docherty
PII: S1440-2440(16)30236-5
DOI: http://dx.doi.org/doi:10.1016/j.jsams.2016.11.001
Reference: JSAMS 1422
To appear in: Journal of Science and Medicine in Sport
Received date: 16-4-2016
Revised date: 25-10-2016
Accepted date: 15-11-2016
Please cite this article as: Hall Emily A, Docherty Carrie L.Validity of clinical outcome
measures to evaluate ankle range ofmotion during theweight-bearing lunge test.Journal
of Science and Medicine in Sport http://dx.doi.org/10.1016/j.jsams.2016.11.001
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http://dx.doi.org/doi:10.1016/j.jsams.2016.11.001
http://dx.doi.org/10.1016/j.jsams.2016.11.001
1 
 
Validity of clinical outcome measures to evaluate ankle range of motion during the weight-bearing 
lunge test. 
 
Emily A. Hall, PhD, ATC;
 a
 Carrie L. Docherty, PhD, ATC, FNATA
b
 
a
Department of Orthopaedics and Sports Medicine, Morsani College of Medicine, 13220 USF Laurel 
Drive, MDC106, Tampa, FL 33612 
b
Department of Kinesiology, School of Public Health, 1025 E. 7
th
 St., Bloomington, IN 47405 
 
Corresponding Author: Emily A. Hall, eannehall@health.usf.edu 
 
Word Count: 2,038 
Abstract Word Count: 241 
# Tables: 1 
# Figures: 3 
 
Validity of clinical outcome measures to evaluate ankle range of motion during the weight-
bearing lunge test. 
 
 
2 
 
Objectives: To determine the concurrent validity of standard clinical outcome measures 
compared to laboratory outcome measure while performing the weight-bearing lunge test 
(WBLT). 
Design: Cross-sectional study. 
Methods: Fifty participants performed the WBLT to determine dorsiflexion ROM using four 
different measurement techniques: Dorsiflexion angle with digital inclinometer at 15cm distal to 
the tibial tuberosity (°), dorsiflexion angle with inclinometer at tibial tuberosity (°), maximum 
lunge distance (cm), and dorsiflexion angle using a 2D motion capture system (°). Outcome 
measures were recorded concurrently during each trial. To establish concurrent validity, Pearson 
product-moment correlation coefficients (r) were conducted, comparing each dependent variable 
to the 2D motion capture analysis (identified as the reference standard). A higher correlation 
indicates strong concurrent validity. 
Results: There was a high correlation between each measurement technique and the reference 
standard. Specifically the correlation between the inclinometer placement at 15cm below the 
tibial tuberosity (44.9° ± 5.5°) and the motion capture angle (27.0° ± 6.0°) was r=0.76 
(p=0.001), between the inclinometer placement at the tibial tuberosity angle (39.0° ± 4.6°) and 
the motion capture angle was r=0.71 (p=0.001), and between the distance from the wall clinical 
measure (10.3 ± 3.0cm) to the motion capture angle was r=0.74 (p=0.001). 
Conclusions: This study determined that the clinical measures used during the WBLT have a 
high correlation with the reference standard for assessing dorsiflexion range of motion. 
Therefore, obtaining maximum lunge distance and inclinometer angles are both valid 
assessments during the weight-bearing lunge test. 
3 
 
Keywords: inclinometer; motion capture analysis; lunge distance; concurrent validity; reference 
standard 
 
4 
 
INTRODUCTION 
An increased number of healthcare practitioners are utilizing evidence-based medicine 
principles in their clinical practice. Evidence-based medicine integrates research, clinical 
expertise, and patient preference to guide clinical decision making.
1
 Researchers are encouraged 
to investigate clinical measures or techniques that are commonly used or most accessible in the 
clinical setting.
2
 Incorporating clinical measures into research will ensure these measures and 
techniques are transferred to the clinical setting. For many injuries to the lower extremity, 
assessing dorsiflexion range of motion is essential to identify risk factors
3
 or alterations in gait or 
landing mechanics.
4
 
The weight-bearing lunge test (WBLT) is a clinical test that measures dorsiflexion range 
of motion of the ankle joint. The WBLT has been used to detect range of motion deficits in 
those with chronic ankle instability
5
 and track progress in improving range of motion during 
rehabilitation protocols.
6
 The WBLT has been established as a reliable measure,
7-9
 however, no 
current research exists comparing the WBLT to a laboratory measure of joint kinematics. 
Based off a recent systematic review,
10
 a variety of procedural differences have been utilized in 
published research when obtaining data on the WBLT.
8, 11, 12
 Specifically, WBLT data can be 
quantified using either a digital inclinometer or maximum lunge distance from the wall. 
Previous research has determined a high correlation between the angle using a digital 
inclinometer and the distance from the wall,
7
 but the placement of the digital inclinometer has 
also varied between studies (i.e tibial tuberosity
9, 11
 or 15 centimeters distal to the tibial 
tuberosity.
7
) 
Validity is defined as the ‘degree to which an instrument truly measures the construct(s) 
it purports to measure.’
13
 Concurrent validity is a subset of test validity that compares a test with 
5 
 
an established measure. A higher correlation indicates that the test has strong concurrent validity 
with the ‘established’ measure in the literature. The ‘established’ measure for assessing range of 
motion in the laboratory setting is a video motion capture analysis.
14
 There have been no 
concurrent validity studies between the clinical measures and video motion capture analysis 
during the WBLT. Therefore, the purpose of this study is to determine if the clinical measures 
are valid assessments of range of motion compared to the laboratory measures during the weight-
bearing lunge test. 
METHODS 
Fifty participants between the ages of 18-35 were eligible to participate in this study (25 
males, 25 females, 24.2±3.5 years, 172.8±10.3 cm, 76.4±16.6 kg, 43 right foot dominant, and 7 
left foot dominant). Prior to participation, all participants completed a Physical Activity 
Readiness Questionnaire (PAR-Q) and a health history questionnaire. The sample included 
participants with a heterogeneous age, physical activity level, and history of lower extremity 
injury. A heterogeneous sample was employed for this validity study to improve external 
validity regardless of the type of sample tested.
15, 16
 Therefore, the exclusion criteria were 
limited to if they answered yes to any questions on the PAR-Q or if they were unable to perform 
the tests without pain or discomfort. Before participating in the study, all participants read and 
sign an informed consent form approved by the University’s Institutional Review Board for the 
Protection of Human Subjects, which also approved the study. 
 The WBLT was performed using four different measurement techniques: digital 
inclinometer placed at the tibial tuberosity, digital inclinometer placed 15cm distal to the tibial 
tuberosity, a tape measure, and a two-dimensional video camera. Participants performed the 
WBLT on their dominant limb.
17
 The participants lunged forward trying to touch a vertical line 
6 
 
on the wall with their knee while maintaining heel contact with the ground.
7, 18
 Touching the 
vertical lineperpendicular to the floor helped control subtalar joint movement and standardized 
between participants. The contralateral limb was positioned behind the testing limb in a 
comfortable position and hands were placed on the wall in front to maintain stability (Figure 1). 
If they were able to maintain heel and knee contact, they moved their foot away from the wall in 
order to reach maximum dorsiflexion range of motion. Participants performed three practice 
trials followed by 3 test trials. Each dependent variable (angle at 15cm (°), angle at tibial 
tuberosity (°), motion capture angle (°), and maximum lunge distance (cm)) were performed 
concurrently during each trial. Participants were instructed to dorsiflex as far as possible, but no 
encouragement was provided during the testing. The exact procedures for capturing each 
dependent variable is explained in the following paragraphs. 
Using a digital inclinometer (Acumar, Lafayette Instruments, Lafayette, IN) at two 
different positions, maximal dorsiflexion was determined. Based on previous research, the 
inclinometer positions were 1) at the tibial tuberosity
9, 11
 and 2) at 15cm distal to the tibial 
tuberosity.
7
 Each position was marked with a pen and the center of the inclinometer was placed 
at that position. Prior to each participant, the inclinometer was calibrated to a 90° angle using a 
level. During each trial, the value was stored in the inclinometer and transferred to an Excel 
worksheet to prevent investigator recall bias. Assessor was blinded to the values after all three 
trials were complete. The value from the inclinometer at their maximal dorsiflexion position was 
recorded and the mean of the three test trails was used for statistical analysis. 
 Maximum lunge distance was recorded using a standard tape measure secured to the 
floor. The measurement was obtained between the great toe and the wall, to the nearest 0.1cm. 
7 
 
The value was recorded after each trial and the mean of three test trials was used for statistical 
analysis. 
 A two-dimensional motion capture analysis (MAXTraq 2D, Innovision Systems Inc, 
Columbioville, MI) was employed as the reference standard. Reflective markers were placed at 
the tibial plateau, lateral malleolus, and base of the 5
th
 metatarsal. For calibration purposes, data 
were captured for 5 seconds when the participant stood with their feet shoulder width apart. The 
difference between the standing trial and each maximum dorsiflexion range of motion during the 
WBLT trials were calculated and the mean of the three test trials was used for statistical analysis. 
 To establish concurrent validity, Pearson product-moment correlation coefficients (r) 
were conducted, comparing each dependent variable to the reference standard (2D motion 
capture analysis). Distance to angle ratio was also calculated from the line of best fit equation on 
the scatter plot. Finally, analyses between each angular clinical measure to the reference 
standard were explored using the Bland Altman plots. All statistical analyses were performed 
using SPSS Version 22 (SPSS, Inc., Chicago, IL). Correlation coefficients were interpreted in 
the following manner based on previous literature: negligible (0.0 < r < 0.3), low (0.3 ≤ r < 
0.50), moderate (0.5 ≤ r < 0.7), high (0.7 ≤ r ≤ 0.9), or very high (0.9 ≤ r ≤ 1.0).
19 
RESULTS 
Descriptive data with means, standard deviations, mean differences, and 95% limits of 
agreement were calculated for each outcome measure (Table 1). There was a high correlation 
between each measure and the reference standard. Specifically, the correlation between the 
angle when the inclinometer was placed at 15cm below the tibial tuberosity and the motion 
capture angle was r=0.76 (p=0.001) (Figure 2a). The correlation between the angle when the 
inclinometer was placed at the tibial tuberosity and the motion capture angle was r=0.71 
8 
 
(p=0.001) (Figure 2b). The correlation when the distance from the wall measure was related to 
the motion capture angle was r = 0.74 (p=0.001) (Figure 2c). After analyzing the distance to 
angle ratio, we determined that for every 2cm distance from the wall, there was an increase in 1 
degrees compared to the motion capture angle. The Bland Altman plots are located in Figure 3 
for the inclinometer angle at 15cm and inclinometer angle at tibial tuberosity. 
DISCUSSION 
This was the first known study to evaluate the concurrent validity of clinician-oriented 
outcomes compared to their laboratory-oriented outcomes during the WBLT. Previously, high 
concurrent validity has been established between an electrogoniometer and motion capture 
analysis of hip, knee, and ankle during ballet movements,
14
 as well as high concurrent validity 
between a digital inclinometer and universal goniometer at the hip.
20
 This is the first study to 
assess the validity of ankle range of motion during the WBLT. These results indicate that the 
both inclinometer angles and the maximum lunge distance have a high correlation with the 
motion capture angle (ranging from 0.71 to 0.76). Therefore, any can be utilized as valid clinical 
measures when performing the WBLT. Since a digital inclinometer is not always available in 
the clinical setting, measuring maximum lunge distance from the wall may be another valid 
option. Using a tape measure is also a cheaper alternative to purchasing a digital inclinometer. 
Previous research found that for every 1 centimeter away from the wall, there was a 3° increase 
in ankle dorsiflexion.
7
 In our study, for every 1 centimeter away from the wall, there was a 2° 
increase in ankle dorsiflexion. 
When comparing the inclinometer and reference standard, the discrepancy in values of 
the angular measures could be a result of the calibration method used for each measure. This 
was confirmed using the Bland Altman plots. We determined a systematic bias for each clinical 
9 
 
measure compared to the reference standard. When the inclinometer was placed at 15cm distal 
to the tibial tuberosity a bias of 17.9º resulted. When the inclinometer was placed on the tibial 
tuberosity a bias of 12.0º was identified. As described in the methods, the 2D motion capture 
angle was standardized to each participant’s standing lower limb angle. However, based on 
previously published procedures, the inclinometer measures were standardized to a 90° angle 
using a level.
9, 11
 We hypothesize that this calibration difference was the primary factor in 
creating a systematic bias. Future research should consider calibrating the digital inclinometer to 
the participant’s quiet stance. 
There were also differences between the angle measured at the tibial tuberosity and 15 
centimeters below the tibial tuberosity. This could be due to the placement of the inclinometer 
on the tibial tuberosity slightly varied between participants depending how close the participant’s 
foot was to the wall. The investigator found it difficult to place the digital inclinometer without 
obstruction on the tibial tuberosity in participants with less ankle range of motion. This 
obstruction occurred when participants were about 6 centimeters from the wall and closer. 
While one study
9
 that placed the inclinometer on the tibial tuberosity using the knee-to-wall 
technique reported that there was no inclinometer obstruction. Another previous study
11
 which 
had a similar obstruction issue, performed a modified weight bearing lunge test but did not 
perform the knee-to-wall technique. They instructed participants to lunge forward with their 
contralateral limb in front. While this modified technique eliminates the obstruction issues, it 
has not been consistently used in previous literature and subsequently was not investigated in the 
current study. 
One limitation to this study was the experience of the investigator performingthe WBLT. 
Investigator was considered to be a novice rater with only 6 months of experience, although, 
10 
 
previous research found that difference in skill level and experience of the raters did not appear 
to influence the reliability of the WBLT.
7
 Another possible limitation was that we did not 
control for posterior talar displacements, foot length, or leg length because previous research did 
not identify significant relationships on the WBLT performance.
8
 Recall bias was also present in 
this study during recording of the distance from the wall. The inclinometer angles and 2D 
motion capture angles were stored in the device and processed after the participant completed the 
trials. Future research should further analyze the differences in values of the inclinometer and 
motion capture angles when it is standardized to the participant’s standing calibration. Another 
method to standardize between patients would be to include taking a percentage of the 
participants’ shank length instead of the constant of 15cm. 
CONCLUSION 
 Using valid clinical measures is an important aspect of evidence-based clinical practice. 
This study determined that the clinical measures used during the WBLT have a high correlation 
with the laboratory measure of assessing dorsiflexion range of motion. Therefore, obtaining 
maximum lunge distance and inclinometer angles are valid assessments during the weight-
bearing lunge test. 
PRACTICAL IMPLICATIONS 
 Incorporating clinical measures into research will ensure these measures and techniques 
are transferred to the clinical setting. 
 Maximum lunge distance and inclinometer angles are valid clinical measures during the 
weigh-bearing lunge test. 
 Obtaining valid clinical measures will provide better patient care. 
ACKNOWLEDGMENTS 
11 
 
 No financial assistance was received for this study. 
12 
 
REFERENCES 
 
1. Steves R, Hootman JM. Evidence-Based Medicine: What Is It and How Does It Apply to Athletic 
Training? J Athl Train. 2004; 39(1):83-87. 
2. McKeon PO, McKeon JMM, Mattacola CG, et al. Finding context: a new model for interpreting 
clinical evidence. Int J Athl Ther Train. 2011; 16(5):10-13. 
3. Willems T, Witvrouw E, Delbaere K, et al. Intrinsic risk factors for inversion ankle sprains in 
females – a prospective study. Scand J Med Sci Sports. 2005; 15:336-345. 
4. Fong C-M, Blackburn JT, Norcross MF, et al. Ankle-dorsiflexion range of motion and landing 
biomechanics. J Athl Train. 2011; 46(1):5. 
5. Hoch MC, Staton GS, Medina McKeon JM, et al. Dorsiflexion and dynamic postural control 
deficits are present in those with chronic ankle instability. J Sci Med Sport. 2012; 15(6):574-579. 
6. Hoch MC, McKeon PO. The effectiveness of mobilization with movement at improving 
dorsiflexion after ankle sprain. J Sport Rehabil. 2010(19):226-232. 
7. Bennell K, Talbot R, Wajswelner H, et al. Intra-rater and inter-rater reliability of a weight-bearing 
lunge measure of ankle dorsiflexion. Aust J Physiother. 1998; 44(3):175-180. 
8. Hoch MC, McKeon PO. Normative range of weight-bearing lunge test performance asymmetry in 
healthy adults. Man Ther. 2011; 16(5):516-519. 
9. Konor MM, Morton S, Eckerson JM, et al. Reliability of three measures of ankle dorsiflexion 
range of motion. Int J Sports Phys Ther. 2012; 7(3):279. 
10. Powden CJ, Hoch JM, Hoch MC. Reliability and minimal detectable change of the weight-
bearing lunge test: A systematic review. Manual therapy. 2015; 20(4):524-532. 
11. Basnett CR, Hanish MJ, Wheeler TJ, et al. Ankle Dorsiflexion Range of Motion Influences 
Dynamic Balance in Individuals with Chronic Ankle Instability. Int J Sports Phys Ther. 2013; 
8(2):121-128. 
12. O'Shea S, Grafton K. The intra and inter-rater reliability of a modified weight-bearing lunge 
measure of ankle dorsiflexion. Man Ther. 2013; 18(3):264-268. 
13. de Vet HCW, Terwee CB, Mokkink LB. Validity, Chapter 6, in Measurement in Medicine: A 
Practical Guideed^eds. Cambridge, Cambridge University Press, 2011. 
14. Bronner S, Agraharasamakulam S, Ojofeitimi S. Reliability and validity of electrogoniometry 
measurement of lower extremity movement. J Med Eng Technol. 2010; 34(3):232-242. 
15. Docherty CL, Rybak-Webb K. Reliability of the anterior drawer and talar tilt tests using the 
LigMaster joint arthrometer. J Sport Rehabil. 2009(18):389-397. 
16. Wikstrom EA. Validity and reliability of Nintendo Wii Fit balance scores. J Athl Train. 2012; 
47(3):306. 
17. Vicenzino B, Branjerdporn M, Teys P, et al. Initial changes in posterior talar glide and 
dorsiflexion of the ankle after mobilization with movement in individuals with recurrent ankle 
sprain. J Orthop Sports Phys Ther. 2006; 36(7):464-471. 
18. Hoch MC, Staton GS, McKeon PO. Dorsiflexion range of motion significantly influences 
dynamic balance. J Sci Med Sport. 2011; 14(1):90-92. 
19. Hinkle DE, Wiersma W, Jurs SG. Correlation: A Measure of Relationship, Chapter 6, Chapter 6, 
in Applied statistics for the behavioral sciencesed^eds. 2nd ed. Boston, Houghton Mifflin 
Company, 1988. 
20. Roach S, San Juan JG, Suprak DN, et al. Concurrent validity of digital inclinometer and universal 
goniometer in assessing passive hip mobility in healthy subjects. Int J Sports Phys Ther. 2013; 
8(5):680-688. 
 
 
13 
 
Table 1: Means, standard deviations (SD), mean differences, and 95% limits of agreement for 
each outcome measure 
 
14 
 
Figure 1: Set-up of the Weight-Bearing Lunge Test (WBLT). All four measures were performed 
at the same time. A) 2D motion capture angle, B) Inclinometer 15cm below the tibial tuberosity, 
C) Inclinometer at the tibial tuberosity, and D) Distance from the wall. 
 
Figure 2: Scatter plots of the Pearson Product Moment Correlation of A) 2D versus Inclinometer 
Angle at 15cm distal to the tibial tuberosity, B) 2D versus Inclinometer Angle at Tibial 
Tuberosity, and C) 2D angle versus the distance from the wall. 
Figure 3: Bland-Altman Level of Agreement for comparing A) 2D motion capture analysis and 
the inclinometer angle at 15cm distal to the tibial tuberosity and B) 2D angle and the 
inclinometer angle at the Tibial Tuberosity (TibTub). The solid line represents the mean 
difference (bias) and the dotted lines indicate 1.96 x SD of the mean difference (95% CI). 
 
15 
 
Table 1: Means, standard deviations (SD), mean differences, and 95% limits of agreement for each 
outcome measure 
Outcome Measure Mean ± SD Mean Difference to 
Reference Standard 
95% Limits of Agreement 
(Upper, Lower) 
2D Motion Capture Angle (°) 27.0 ± 6.0 -- -- 
Angle @ 15cm (°) 44.9 ± 5.5* 17.9 ± 4.0 25.8, 10.1 
Angle @ Tibial Tuberosity (°) 39.0 ± 4.6* 12.0 ± 4.3 20.4, 3.6 
Maximum Lunge Distance (cm) 10.3 ± 3.0* 16.7 ± 4.3 25.2, 8.2 
* indicates a significant correlation between the outcome measure and the 2D motion capture angle 
 
Figure 1: Set-up of the Weight-Bearing Lunge Test (WBLT). All four measures were performed 
at the same time. A) 2D motion capture angle, B) Inclinometer 15cm below the tibial tuberosity, 
C) Inclinometer at the tibial tuberosity, and D) Distance from the wall.
A
B
C
D
Figure 2: Scatter plots of the Pearson Product Moment Correlation of A) 2D versus Inclinometer 
Angle at 15cm distal to the tibial tuberosity, B) 2D versus Inclinometer Angle at Tibial
Tuberosity, and C) 2D angle versus the distance from the wall.
10.00
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Figure 3:Bland-Altman Level of Agreement for comparing A) 2D motion capture analysis and 
the inclinometer angle at 15cm distal to the tibial tuberosity and B) 2D angle and the 
inclinometer angle at the Tibial Tuberosity (TibTub). The solid line represents the mean 
difference (bias) and the dotted lines indicate 1.96 x SD of the mean difference (95% CI). 
B 
D
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Mean of 2D and TibTub 
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Mean of 2D and 15cm
 
 
Figure 3: Bland-Altman Level of Agreement for comparing A) 2D motion capture analysis and 
the inclinometer angle at 15cm distal to the tibial tuberosity and B) 2D angle and the 
inclinometer angle at the Tibial Tuberosity (TibTub). The solid line represents the mean 
difference (bias) and the dotted lines indicate 1.96 x SD of the mean difference (95% CI). 
B 
D
if
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Mean of 2D and TibTub 
B 
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(2
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5c
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Mean of 2D and 15cm
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