the influence of q-angle and muscle strength on the stair kinetics and kinematics of women

109 Pages·2007·0.9 MB·English

The Influence of Q-Angle and Gender on the Stair-Climbing Kinetics and Kinematics of
the Knee

By

Alexis Marion Cartwright

A thesis
presented to the University of Waterloo
in fulfillment of the
thesis requirement for the degree of
Master of Science
in
Kinesiology

Waterloo, Ontario, Canada 2007

© Alexis Marion Cartwright 2007
Author’s Declaration

I hereby declare that I am the sole author of this thesis. This is a true copy of the thesis, including
any required final revisions, as accepted by my examiners.

I understand that my thesis may be made electronically available to the public.

Alexis Marion Cartwright

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Abstract

Background: Knee joint motion and quadriceps activity play a crucial role in all lower limb
tasks, especially those which are highly dynamic and weight-bearing. Due to anatomical
differences between men and women such as height, leg length, and hip width, alignment and
mechanics of the lower limb are different between males and females. An anatomical variable
which is associated with alignment in the lower limb is the quadriceps muscle angle (q-angle).
The purpose of this study is to determine if there is a relationship between q-angle, activity of the
quadriceps and hamstring muscles and the kinetics and kinematics of the knee during stair-
climbing. An investigation on the reliability of q-angle measurements was also made prior to the
primary study.

Methods: To test the interclass reliability of q-angle measurements, three individuals measured
the q-angle on 20 subjects. The primary researcher measured the same twenty individuals on
three separate days to determine intra-rater reliability.
The primary study involved 10 male and 10 female subjects completing 20 stair-climbing trials
(10 ascent, 10 descent). Kinematic and kinetic data were collected on the lower limbs as well as
electromyography (EMG) on two quadriceps muscles and one hamstring muscle. Knee joint
peak and occurrence of peak moments, average EMG amplitude and peak and occurrence of
peak EMG were analyzed by gender and high and low q-angle. A two way analysis of variance
(ANOVA) was used to test the statistical significance of each measured variable (α = 0.05).

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Results & Discussion: The inter-rater reliability for q-angle was low (0.27-0.78) but the intra-
rater reliability showed q-angle measurements to be very reliable (0.80-0.95). For study 2, it was
found that females had increased vastus lateralis and vastus medialis peak EMG and average
EMG amplitudes for stair ascent and descent compared to males. Furthermore, for descent only,
females demonstrated having delayed occurrence of peak EMG for vastus lateralis and biceps
femoris, and exhibited an increased peak knee extension moment and a decreased peak knee
adduction moment compared to males. For q-angle, there was a significant difference found for
biceps femoris occurrence of peak EMG during descent, with the high q-angle group having
delayed occurrence of peak. For ascent, the high q-angle group had significantly increased
average vastus lateralis EMG and an earlier occurrence of knee abduction moment. Q-angles
were found to be higher for women compared to men.

Conclusion: This study confirms that gender differences do exist in knee moment and thigh
EMG parameters with stair ascent and stair descent. With the high incidence of significant
findings for the quadriceps muscle, further investigation is warranted to determine if a
relationship does exist between q-angle and knee joint function. It would also be recommended
that hip mechanics be included in future studies due to the difference seen in adduction moments
at the knee.
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Acknowledgements

I would like to thank my supervisor, Dr. Jennifer Durkin, for her time and expertise with this
thesis. As well as all of the wonderful code to get me through the mounds of data!

I would like to thank, Rob Parkinson for all his help and expertise with coding, EMG and school
in general. I would also like to thank Jennifer Kelly for all her help with my collections. The
participants or I would not have survived without you!

I would also like to thanks Jon Donnelly for his help and support and cooperation with lab space
and time.

A huge thank-you goes out to my friends Diane Gregory and Nadine Dunk for all of your
support and help. The last two years would not have been the same without you.

Special thanks to my Husband, Andrew Lister who has supported me and tolerated me through
the many ups and downs of the last two years. You have been there emotionally and financially
without question. And you still asked me to marry you! Thank you for being my best friend and
the best shoulder to cry on.

Finally I would like to send extra special thanks to my parents, Paul Cartwright and Mary
Radford for their emotional and financial support. You have been amazing role models, advisors
and friends! I could not have done any of this without you!

THANK YOU!

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Table of Contents

Abstract…………………………………………………………………………………... iii
List of Tables..……………………………………………………………………………. viii
List of Figures..…………………………………………………………………………… ix
List of Appendices………………………………………………………………...…….... x

1. Introduction….................................................................................................................1
1.1 Statement of Purpose 2
1.2 Problem Investigated 3
1.3 Statement of Hypothesis 3

2. Review of Literature……………………………………………..……………………. 5
2.1 Knee Osteoarthritis and Gender 5
2.2 Stair Kinematics 8
2.3 Stair Kinetics 12
2.3.1 Joint Loading 12
2.3.2 Moments Acting on the Knee 15
2.3.3 Muscle Activity and Strength 18
2.4 Quadriceps Muscle Angle 22

3. Study I: Repeatability of Q-Angle Measurements: Interclass and
Intraclass Correlations…………………………………………………………………26
3.1 Methods 26
3.1.1 Subjects 26
3.1.2 Equipment and Protocol 26
3.1.3 Data & Statistical Analysis 27
3.2 Results 28
3.3 Discussion 30
3.4 Conclusion 33

4. Study II: The Influence of Q-Angle and Gender on the Stair-Climbing
Kinetics and Kinematics of the Knee ….…………………………………………….. 34
4.1 Methods 34
4.1.1 Subjects 34
4.1.2 Equipment and Protocol 34
4.1.3 Data Analysis 38
4.1.4 Statistical Analysis 41
4.2 Results 42
4.2.1 Q-Angle 42
4.2.2 Ascent 43
4.2.3 Descent 46
4.3 Discussion 50
4.3.1 Q-Angle 50
4.3.2 Gender 57
4.3.2.1 Kinetics 58
vi
4.3.2.2 Electromyography (EMG) 63
4.3.3 Limitations 68

6. Conclusions……………………………………………………………………………. 70

7. References...…………………………………………………………...……………..... 72

Appendix 1
Appendix 2
Appendix 3
Appendix 4
Appendix 5
Appendix 6
Appendix 7
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List of Tables

Table 3.1……………………………………………………………………………………… 29
Individual Q-Angle Measurements: Mean Q-Angle Measurements and Intraclass Correlation
Coefficients

Table 3.2……………………………………………………………………………………… 30
Individual Q-Angle Measurements: Mean Q-Angle Measurements and Interclass Correlation
Coefficients

Table 4.1………………………………………………………………………………………. 42
Descriptive Statistics for Subjects in Study II.

Table 4.2………………………………………………………………………………………. 43
Q-Angle Values and Means for Male and Female Left and Right Leg

Table 4.3………………………………………………………………………………………. 44
Means and Standard Deviations (SD) for the Dependant Variables Analyzed for the Stair Ascent
Trials.

Table 4.4………………………………………………………………………………………. 46
Means and Standard Deviations (SD) for the Dependant Variables Analyzed for the Stair
Descent Trials.

Table 4.5………………………………………………………………………………………. 62
Time in Contact with the Force Plate.
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List of Figures

Figure 2.1……………………………………………………………………………………..…23
Q-Angle and Vectors Created by the Anterior Superior Iliac Spine (ASIS), Mid-Patella (MP) and
Tibial Tuberosity (TT).

Figure 3.1…………………………………………………………………………………..……27
Q-Angle and Marker Locations: Anterior Superior Iliac Spine (ASIS), Mid-Patella (MP) and
Tibial Tuberosity (TT)

Figure 4.1……………………………………………………………………………….…….…36
Experimental Setup for Maximum Voluntary Exertion (MVE) Trials
(0° = leg in full extension)

Figure 4.2………………………………………………………………………………….…... 37
Staircase used for the ascent descent trials.

Figure 4.3………………………………………………………………………………...….… 38
Experimental Setup for the Data Collection.

Figure 4.4……………………………………………………………………………….……... 39
Q-Angle and Marker Locations: Anterior Superior Iliac Spine (ASIS), Mid-Patella (MP) and
Tibial Tuberosity (TT) (Livingston and Mandigo, 1999).

Figure 4.5………………………………………………………………………………..…..… 45
The Mean Values for Peak EMG and Average EMG for the Vastus Lateralis (VL) and Vastus
Medialis (VM) for Ascent.

Figure 4.6………………………………………………………………………………….….. 48
The Mean Values for Peak EMG and Average EMG for the Vastus Lateralis (VL), Vastus
Medialis (VM) and Biceps Femoris (BF) for Descent between Genders.

Figure 4.7…………………………………………………………………………………...… 48
The Mean Values for Occurrence of Peak for the Vastus Lateralis (VL) and Biceps Femoris (BF)
between Genders.

Figure 4.8…………………………………………………………………………………..… 49
The Mean Values for Peak Knee Extension and Adduction Moments for Stair Descent between
Genders.

Figure 4.9………………………………………………………………………………….…. 52
The Mean Q-Angle Values Average Biceps Femoris EMG for Stair Ascent.

Figure 4.10………………………………………………………………………………….…52
The Mean Q-Angle Values for Occurrence of Peak Knee Abduction Moment for Stair Ascent.

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Figure 4.11…………………………………………………………………………………… 53
The Mean Q-Angle Values for Occurrence of Peak Biceps Femoris EMG for Stair Descent.

Figure 4.12………………………………………………………………………………….... 55
The Mean Values for Peak Knee Flexion Moment by Q-Angle and Gender.

Figure 4.13…………………………………………………………………………………… 56
The Mean Values for Peak Knee Adduction Moment by Q-Angle and Gender.

Figure 4.14…………………………………………………………………………………… 60
Knee Angle Profiles during Ascent for Males and Females.

Figure 4.15…………………………………………………………………………………… 60
Knee Moment Profiles during Ascent for Males and Females.

Figure 4.16………………………………………………………………………………….... 61
Knee Angle Profiles during Descent for Males and Females.

Figure 4.17…………………………………………………………………………………... 61
Knee Moment Profiles during Descent for Males and Females.
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