Correlation between conventional clinical tests and a new movement assessment battery - Bachelor thesis
Despite the complexity of movements performed in sports, physical examination is today done by conventional tests that evaluate joints and muscles individually (e.g. Smith press test, Figure1). Our study used a new movement assessment battery of 20 reach tests, which incorporates the complexity and diversity of natural human movements, taking into consideration that joints are interdependent in a movement and that the planes and sequences of a movement change during its performance. The purpose of this study was to determine whether or not there is a correlation between conventional mobility tests and the new assessment battery.
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Correlation between conventional clinical tests and a new movement assessment battery - Bachelor thesis
1. Bachelor Thesis
Correlation between conventional clinical tests and a new
movement assessment battery
May, 2013
Patrick Anderson (patrickja@student.nih.no)
Stavros Litsos (stavrosl@student.nih.no)
2. 1
Abstract
The purpose of this study was to determine on whether or not there is a correlation between
established conventional tests and the new movement assessment battery. Eight males (height,
182.7 ± 6.1 cm; body mass, 80.2 ± 9.3 kg) participated in this study. A mobility performance mat
was used as a foundation for all the 20 movements the subjects was instructed to do, each
movement performed 3 times. Subsequent to the mobility test, the subjects did a series of
conventional test. Range of motion was then measured using a goniometer. No participants
withdrew from the study. The conventional tests were completed as the protocol dictated. No
correlation between mobility rotation tests and internal/external hip rotation was found. Although
there was a significant correlation between Test 8 and the Thomas test on the right hip, there was
no significant correlation between the overhead reaches and the results from the Thomas tests. A
correlation between floor reaches and standing left ankle dorsiflexion was found, while no
significant correlation was found for the right ankle. A higher correlation between overhead
reaches and ankle dorsiflexion compared to floor reach and ankle dorsiflexion was registered. In
both cases, a significant correlation for both right and left leg, with the left achieving higher
correlation values than the right was found. Dominant leg has an influence on the correlations,
although not known if positive or negative.
Keywords
Mobility tests, conventional tests, biomechanical analysis, physical examination, correlations.
4. 3
Despite the fact of integrating a functional approach by incorporating the principles of
PNF (proprioceptive neuromuscular facilitation), muscle synergy and motor learning during the
last 20 years, the absence of multifactorial functional physical examination, that consider the
human body as a kinetic linked system of joints interdependence on movement, makes it
challenging to refer to a functional factor analysis protocol (Cook, Burton, & Hoogenboom,
2006).
Although conventional clinical tests single out specific joints for testing, the results
provided by these tests can be relatively inconsistent among examiners. In a previous study by
Jason Peeler (Jason D.Peeler, 2008), three certified athletic therapists measured the joint knee
angle in a modified Thomas Test on 57 healthy participants, two times. The study showed a
standard deviation of 12° among the examiners and a method error of 6°. This raises the question
of the reliability of tests measuring ranges of motion in various joints. The inconsistency of
examiners when establishing joint lines, locating important landmarks and aligning axis of
rotations contributes to a loss of reliability. Consequently, this has an immediate effect on the
validity.
To address the lack of specificity and for improved functional application a new
functional mobility test battery is under development (Table 1). In contrast to traditional tests,
this test battery incorporates how different parts of the body have an interdependent relationship
in a standing position when performing certain movements. Twenty different tests lay the
foundation of the screen that is measured in centimetres or degrees. The results from each
individual test are carefully combined to create a functional mobility profile. Previous studies
suggest that applying a test characterized by dynamic movement, such us the mobility tests
performed on our study, can give access to multiple domains of function. This can also indicate
athletes at risk of injury with a pre-seasonal assessment (Plisky, Rauh, Kaminski, & Underwood,
2006). Several other studies have showed that joints are interdependent during movement (John
McMullen, 2000; Levangie & Norkin, 2005; Marta B. Villamila, Luciana P. Nedela, Carla
M.D.S Freitasa, 2011; McLester, John, Pierre, 2008). So in order to apply a physical evaluation
that is able to qualify human movement, a similarity between training and testing procedures is
essential (Zatsiorsky., 2000, p. 9).
The purposes of this study were (1) to conduct mobility tests with the novel mobility
screen test battery and with selected conventional tests used to determine joint mobility in
5. 4
patients; (2) to determine on whether or not there is a correlation between established
conventional tests and the new mobility test battery; and (3) to quantify the repeatability of test
results in conventional tests when executed by different examiners. We hypothesized that (i)
external rotation in the left hip would correlate with the performance in test 14; (ii) hip extension
measured in the Thomas test would correlate with the overhead reach tests (tests 2,4,6,8,16); (iii)
results from a conventional standing dorsiflexion test would correlate with the floor reach tests
(test 1,3,5,7,9,15); and (iv) that the single leg stance leg results from the conventional standing
dorsiflexion tests would correlate with the mobility overhead reach tests (tests 2,4,6,8,10,16).
6. 5
Method
Eight males (height, 182.7 ± 6.1 cm; body mass, 80.2 ± 9.3 kg) participated in this study. Prior to
the experiment, the subjects were informed about the risks of participating, the purpose and
significance of the study and details surrounding data collection. Written informed consent was
obtained from all the subjects. No participants withdrew from the study.
Participants first executed 20 movements according to the new mobility test screen and
their joint mobility was then examined using conventional tests. In the mobility test screen the
participant’s task was to start from a standardized starting posture and then reach or rotate as far
as possible in different directions. A detailed description of each task is shown in Table 1 and in
the Appendix 2. A custom designed mobility performance mat was used to determine the reach
distance for the 20 movements the subjects were instructed to do. The mat has an illustration of a
circular co-ordinate system with origin in the centre. Each 10 cm interval is marked with a circle
and vectors for every 45° to the left and right are marked (L/R45, L/R90 and L/R135). The
anterior and posterior vectors are marked as A0 and P180. The vectors printed on the mat guides
the subjects’ movements. The subjects executed twenty different movements with three
repetitions each. The variables obtained in this test used to quantify the subjects’ mobility were
the reach distance in centimetres and the rotation angles in degrees. If a subject failed one of the
repetitions, the recording stopped. The subject was then instructed to start over.
Subsequent to the mobility tests, the subjects did a series of conventional test on a
physio-bench, two times, measured first by a sport biology student and second by a
physiotherapist. The physiotherapeutic Thomas test indicated the passive range of extension in
each hip the passive range of internal/external hip rotation was measured when the subjects were
in a prone position and seated position, with the knee in 90-degree flexed position. Ankle
dorsiflexion was obtained passively in both a supine and standing position in two positions; A
goniometer was used to measure the different ranges of motion for each test and thus the results
was given in degrees.
All the movements were completed successfully with at least three valid repetitions. The
second trial of the conventional tests had to be rescheduled for another day. However, this also
was completed successfully, although without a warm-up protocol executed pre-trail. The
physiotherapist did all the measuring for the second trail. The results from the first and second
trail of the conventional tests are used to calculate the differences between the two examiners.
7. 6
Microsoft Excel (Microsoft Norge AS, 1366 Lysaker, Norway) was used to graphically
visualize ranges of motion of the movements performed on the mobility performance mat and the
results from the conventional tests and to calculate Pearson correlations between test variables. A
Pearson correlation tests was calculated between the subjects’ individual results in the mobility
screen and their results from the conventional tests. With eight test-subjects, a correlation above r
= 0.67 can be considered as significant at the p = 0.05 level.
8. 7
Table 1: Description of each movement in the functional movement screen.
Functional
Movement
Patterns
–
Description
of
movement
Test
nr.*
Combined
Planes
Description
1
L
SLS
L
arm
R45
reach
to
floor
Left
leg
standing,
left
arm
is
reaching
as
far
as
possible
along
the
R45
vector
on
the
floor.
2
L
SLS
R
arm
L135
overhead
reach
Left
leg
standing,
right
arm
is
reaching
as
far
back
as
possible
along
the
L135
vector,
above
the
head.
3
L
SLS
R
arm
L45
reach
to
floor
Left
leg
standing,
right
arm
is
reaching
as
far
as
possible
along
the
L45
vector
on
the
floor.
4
L
SLS
L
arm
R135
overhead
reach
Left
leg
standing,
left
arm
is
reaching
as
far
back
as
possible
along
the
R135
vector,
above
the
head.
5
R
SLS
R
arm
L45
reach
to
floor
Right
leg
standing,
right
arm
is
reaching
as
far
as
possible
along
the
L45
vector
on
the
floor.
6
R
SLS
L
arm
R135
overhead
reach
Right
leg
standing,
left
arm
is
reaching
as
far
back
as
possible
along
the
R135
vector,
above
the
head
7
R
SLS
L
arm
R45
reach
to
floor
Right
leg
standing,
left
arm
is
reaching
as
far
as
possible
along
the
R45
vector
on
the
floor.
8
R
SLS
R
arm
L135
overhead
reach
Right
leg
standing,
right
arm
is
reaching
as
far
back
as
possible
along
the
L135
vector,
above
the
head.
Pure
Planes
9
L
SLS
B
arms
A0
reach
to
floor
Left
leg
standing,
both
arms
reaching
as
far
as
possible
along
the
A0
vector
on
the
floor.
10
L
SLS
B
arms
P180
overhead
reach
Left
leg
standing,
both
arms
reaching
as
far
back
as
possible
along
the
P180
vector,
above
the
head.
11
L
SLS
B
arms
L90
overhead
reach
Left
leg
standing,
both
arms
reaching
as
far
to
the
side
as
possible
along
the
L90
vector,
above
the
head.
12
L
SLS
B
arms
R90
overhead
reach
Left
leg
standing,
both
arms
reaching
as
far
to
the
side
as
possible
along
the
R90
vector,
above
the
head.
13
L
SLS
B
arms
L
rotational
reach
at
shoulder
height
Left
leg
standing,
both
arms
at
shoulder
height:
rotation
as
far
to
the
left
as
possible.
14
L
SLS
B
arms
R
rotational
reach
at
shoulder
height
Left
leg
standing,
both
arms
at
shoulder
height:
rotation
as
far
to
the
right
as
possible.
15
R
SLS
B
arms
A0
reach
to
floor
Right
leg
standing,
both
arms
reaching
as
far
as
possible
along
the
A0
vector
on
the
floor.
16
R
SLS
B
arms
P180
overhead
reach
Right
leg
standing,
both
arms
reaching
as
far
back
as
possible
along
the
P180
vector,
above
the
head.
17
R
SLS
B
arms
R90
overhead
reach
Right
leg
standing,
both
arms
reaching
as
far
to
the
side
as
possible
along
the
R90
vector,
above
the
head.
18
R
SLS
B
arms
L90
overhead
reach
Right
leg
standing,
both
arms
reaching
as
far
to
the
side
as
possible
along
the
L90
vector,
above
the
head.
19
R
SLS
B
arms
R
rotational
reach
at
shoulder
height
Right
leg
standing,
both
arms
at
shoulder
height:
rotation
as
far
to
the
right
as
possible.
20
R
SLS
B
arms
L
rotational
reach
at
shoulder
height
Right
leg
standing,
both
arms
at
shoulder
height:
rotation
as
far
to
the
left
as
possible.
*Each test is labeled as their respective test number throughout this article.
9. 8
Results
The mean reach distances obtained in the mobility tests are listed in table 2 with their associated
standard deviation. Table 3 shows the average range of motion for each of the conventional tests
representing the maximum passive range of motion in each joint, with exception of standing
ankle dorsiflexion, which is active.
Table 2: Results from the mobility screen.
Mean
results;
Mobility
Screen
Test
nr.
Mean
(cm)
St.
Dev.
(cm)
Test
nr.
Mean
(cm/°)
St.
Dev.
(cm/°)
Test
1
78
10.74
Test
11
81
7.87
Test
2
89
7.69
Test
12
69
11.63
Test
3
67
14.27
Test
13
132°
20.83°
Test
4
62
13.32
Test
14
133°
18.44°
Test
5
80
12.48
Test
15
69
14.95
Test
6
87
6.47
Test
16
69
14.61
Test
7
63
14.84
Test
17
75
14.83
Test
8
63
11.50
Test
18
72
12.72
Test
9
71
12.31
Test
19
132°
19.34°
Test
10
72
13.70
Test
20
142°
20.66°
The external rotation in the left hip did not correlate with the rotation angle in test 14 (r = -0.08,
Table 4). None of the other rotational tests gave a significant correlation (Table 4). Hip extension
as measured by the Thomas test correlated only with the overhead reach distance observed in
test 8 of the new mobility test, the other tests did not correlate significantly (Table 5). In the floor
reach tests, 3 significant correlations were found to the conventional standing dorsiflexion test
(Table 6). The left leg standing and the left leg ankle dorsiflexion during a reach gave significant
correlations. However, this is not the case for the right leg standing and right ankle dorsiflexion.
Table 7 shows the correlations between the single leg stance legs results from the conventional
standing dorsiflexion tests and the mobility overhead reach tests. The correlation for the left leg
were higher than the correlations for the right leg.
10. 9
Table 3: Results from the conventional tests.
Mean
results,
conventional
tests
Test
Mean
(°)
St.
Dev.
(°)
Thomas
tests,
right
hip
8
6.83
Thomas
tests,
left
hip
12
6.00
Pronated
rotation,
right
hip
internal
39
8.83
Pronated
rotation,
right
hip
external
58
5.68
Pronated
rotation,
left
hip
internal
35
9.40
Pronated
rotation,
right
hip
external
58
5.48
Seated
rotation,
right
hip
internal
38
4.39
Seated
rotation,
right
hip
external
48
10.73
Seated
rotation,
left
hip
internal
41
6.02
Seated
rotation,
left
hip
external
49
7.67
Supinated
dorsiflexion,
right
ankle
23
4.57
Supinated
dorsiflexion,
left
ankle
18
4.74
Standing
dorsiflexion,
right
ankle
36
5.06
Standing
dorsiflexion,
left
ankle
36
4.56
Table 4: Correlations between mobility rotation tests and internal/external hip rotation
.Correlation,
rotational
tests
Mobility
and
conventional
tests
Correlations
r
=
Test
13
-‐0.56
Pronated
rotation,
left
hip
internal
Test
14
-‐0.08
Pronated
rotation,
right
hip
external
Test
19
-‐0.02
Pronated
rotation,
right
hip
internal
Test
20
-‐0.19
Pronated
rotation,
right
hip
external
11. 10
Table 5: Correlations between overhead reaches and results from the Thomas tests (hip
extension).
Correlations,
overhead
reach
and
hip
extension
Mobility
and
Conventional
tests
Correlation
r
=
Test
2
0.26
Thomas
tests,
left
hip
Test
4
0.39
Thomas
tests,
left
hip
Test
6
0.45
Thomas
tests,
right
hip
Test
8
0.74
Thomas
tests,
right
hip
Test
10
0.64
Thomas
tests,
left
hip
Test
16
0.64
Thomas
tests,
right
hip
Note: Significant correlations were printed in bold letters.
Table 6: Correlations between mobility floor reaches and standing ankle dorsiflexion.
Correlation,
Floor
reach
and
dorsiflexion
Mobility
and
conventional
tests
Correlations
r
=
Test
1
0.87
Standing
dorsiflexion,
left
ankle
Test
3
0.84
Standing
dorsiflexion,
left
ankle
Test
5
0.56
Standing
dorsiflexion,
right
ankle
Test
7
0.54
Standing
dorsiflexion,
right
ankle
Test
9
0.79
Standing
dorsiflexion,
left
ankle
Test
15
0.55
Standing
dorsiflexion,
right
ankle
Note: Significant correlations were printed in bold letters.
12. 11
Table 7: Correlations between mobility overhead reaches and standing ankle dorsiflexion.
Correlations,
overhead
reaches
and
dorsiflexion
Mobility
and
conventional
tests
Correlations
r
=
Test
2
0.85
Standing
dorsiflexion,
left
ankle
Test
4
0.93
Standing
dorsiflexion,
left
ankle
Test
6
0.43
Standing
dorsiflexion,
right
ankle
Test
8
0.62
Standing
dorsiflexion,
right
ankle
Test
10
0.82
Standing
dorsiflexion,
left
ankle
Test
16
0.61
Standing
dorsiflexion,
right
ankle
Note: Significant correlations were printed in bold letters.
13. 12
Table 8 displays the mean differences and standard deviations of the results between two
examiners performing conventional tests on the subjects. The average indicates the average mean
differences and the average standard deviation among all the tests.
Table 8: Measuring differences between two examiners for the conventional tests.
Measuring
differences
-‐
Conventional
tests
Conventional
Tests
Mean
diff.
(°)
St.
Dev.
(°)
Thomas
tests,
right
hip
7
4
Thomas
tests,
left
hip
5
4
Pronated
rotation,
right
hip
internal
12
8
Pronated
rotation,
right
hip
external
6
8
Pronated
rotation,
left
hip
internal
15
8
Pronated
rotation,
right
hip
external
4
6
Seated
rotation,
right
hip
internal
4
7
Seated
rotation,
right
hip
external
3
13
Seated
rotation,
left
hip
internal
1
6
Seated
rotation,
left
hip
external
5
10
Supinated
dorsiflexion,
right
ankle
6
3
Supinated
dorsiflexion,
left
ankle
2
7
Standing
dorsiflexion,
right
ankle
3
4
Standing
dorsiflexion,
left
ankle
3
5
Average
5
7
14. 13
Discussion
Our result shows no correlation between the pure plane rotations and the internal/external
rotations of the stance hip. One could argue that standing in a fixed position and rotating as far as
possible is greatly determined by the hips ability to rotate. The results presented in Table 4 show
the complete opposite that conventional tests of hip rotational mobility had no correlation with
the ability to perform a rotational test in standing. Our results predict that difficulties in
performing a backhand shot in tennis would not be because of hip rotation limitation, but
because of other parameters. The rotation may have some other origin than the hip joint, perhaps
in the spine or the shoulder complex. These results emphasize the importance of a new test
battery, which evaluate the movement as a whole instead of taking it a part, piece by piece. The
correlation from test 13 and internal left hip rotation yields a correlation of -0.56. It is almost as
if low rotational ranges of motion in the hip increases the ability to rotate the upper body.
However, this correlation was not significant.
The correlations between the overhead reaches and the Thomas tests, as seen in Table 5,
have an average of 0.52 ± 0.18. The lowest correlation being 0.26 for the test 2 and the highest
correlation being 0.74 for the test 8. One would presume that the ability to bend backwards is
greatly affected by the hips ability to extend. After all, bending backwards forces the hip to
extend. As for test 8 and right hip extension, which yielded a correlation of 0.74, which is
significant, one can argue that this is because of the participants’ dominant limb. Even though
the dominant limb was not registered in this study, there is no doubt that the correlation of the
right hip is much better than the left hip. The question then becomes which leg is actually
dominant: is it the left leg with no significant extension during a back bend, or is it the right hip
with a significant participation in the same movement. The average correlation was not
significant suggesting that hip extension may have little influence when performing a back bend.
However, a correlation of 0.52 shows some relationship, but our test group was too small for it to
reach any significance. This strengthens the theory that joints are interdependent during a
complex dynamic movement: when performing a complex movement, like the back bend,
several joints participates. The joints influence each other to a certain degree so that the hip
extension does not become significant for the movement. However, as seen in Table 6, another
joint has a much greater influence on this particular ability.
15. 14
Overhead reaches, or bending backwards, induces a knee flexion to keep the body’s
center of mass within the base of support. This flexion forces an ankle dorsiflexion, because the
foot has to be fixated on the ground for the movement to be valid. As seen in Table 7, there was
a high correlation between the overhead reaches and range of motion in ankle dorsiflexion, the
highest being 0.93 for the test 6 and left ankle dorsiflexion. The average correlation was 0.71 ±
0.18 with a range of 0.5, which is significant. When a high-level athlete experience problems
doing a throw-in in soccer, serve in tennis or a bridge in gymnastics, one could argue that a
physiotherapist should evaluate ankle dorsiflexion. The results from Table 7 suggest that there
are joints that have an indirect role to movement: the backbend is mainly an extension
movement, but an ankle dorsiflexion has a greater influence on this ability than hip extension as
seen in Table 5. There were also indications of asymmetry between the right and left foot.
However, the opposite leg has better correlations compared to Table 5.
This asymmetry between the right and left foot is also observed in Table 6. We see that
despite a relatively small difference in the correlation values achieved between the floor
reaches/standing ankle dorsiflexion and overhead reaches/standing ankle dorsiflexion, the only
significant correlation was found for the left ankle. The reason for this is unknown, but perhaps
the subjects’ dominant limb may alter the results, as seen in Table 5. This has previously been
confirmed by a recent study (Sung & Kim, 2011). It is unknown if the dominant left leg
contributes to a further reach or if it is the non-dominant left leg that contributes.
There is also a slight variation among the test supervisors performing the conventional
tests, shown in Table 8. The average difference was 5 ± 6 degrees of range of motion. This is
comparable of the results given by the study done by Jason Peeler (2008) who found a slightly
higher variation of 12 ± 6 degrees of range of motion. However, our tests examiners consisted of
one experienced physiotherapist and one sport biology student. Even though the student has a
high basic knowledge of anatomy and palpation, it cannot match the clinical experience and
knowledge of an educated physiotherapist. This does not change the fact that there is a variation
when measuring ranges of motion. When measuring joint range of motion in high-level athletes,
there should be a consistency to the results from practitioners. This would increase the efficacy
and the validity of the conventional tests.
16. 15
Conclusions
No correlation was found between the pure plane rotations and the internal/external rotations of
the stance hip during a closed kinetic chain movement. A significant correlation between
overhead reaches/standing ankle dorsiflexion and floor reaches/standing ankle dorsiflexion was
found, with the first mentioned getting higher values than the second. Backwards bending causes
a knee flexion in order to maintain body`s center of mass within the support surface. This flexion
forces an ankle dorsiflexion due to a closed kinetic chain movement. Although leg dominance
was not registered, it is hypothesized that it may alter the results. This points out the importance
of treating the human body as an integrated system, taking into consideration that during a
complex dynamic movement several joints are involved. The variability of the results by
applying conventional tests in order to evaluate the range of motion of the different joints
reduces the validity of these tests even more. In order to be able to capture and predict the quality
of a highly complicated movement pattern performed during a competitive sport, we should first
be able to apply a test battery of which the results are reproducible.However, further research is
necessary to draw any major conclusions. More subjects as well as registration of their dominant
limb is a needed for further analysis.
17. 16
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