ABSTRACT
ELECTROMYOGRAPHIC ANALYSIS ON THE SPECIFIC EXERCISE AND ANGLE OF ACTIVATION OF THE
LOWER TRAPEZIUS MUSCLE IN THE FEMALE COLLEGE-AGED POPULATION
Background: Shoulder pathology relating to subacromial impingement
syndrome has been associated with scapulothoracic dysfunction. The lower
trapezius plays an important role in maintaining normal shoulder kinematics as its function is to posteriorly tilt and upward rotate the scapula during arm elevation. Various lower trapezius strengthening exercises have been investigated; the effectiveness in activating these muscles across multiple exercises is mixed.
Hypothesis: H1: Horizontal abduction with external rotation performed at 125◦ in shoulder abducted position will yield the highest EMG activity. H2: Horizontal abduction with external rotation performed at 45◦in shoulder abducted position will yield the least UT/LT ratio.
Study Design: Cross-sectional study
Methods: Lower and upper trapezius surface EMG activities were collected
from 27 healthy female participants between the ages of 18 to 28 years. Three exercises were measured: horizontal abduction with external rotation, one-arm bent over row, and lawn mower at each angle (45◦, 90◦, and 125◦).
Result: A main effect for mean % MVIC indicate significant finding for
exercise (F(2,52) = 23.32, P < .001) and angle (F(2,52) = 57.74, P < .001). A significant main effect for UT/LT ratios was observed for exercise (F(2,50) = 6.70,
P < .05) and angle (F(2,50) = 6.91, P < .05). There were not interaction for
ii
Conclusion: The studying findings indicate the optimal exercise to
strengthen the LT muscle is horizontal abduction with external rotation when compared to bent over row and lawnmower exercises. Performing these exercises at a 125° results the highest activation across all exercises while exercising at a 45° results in the least amount of LT activity. However, individual who cannot abduct the shoulder to 125°, an alternative angle at 90° may produce moderately high LT activity while maintaining moderate UT muscle activity.
Key Words: lower trapezius, electromyography, scapulothoracic exercise, angle of activation
Word Count: 301 Kelvin Duc Lam
ELECTROMYOGRAPHIC ANALYSIS ON THE SPECIFIC EXERCISE AND ANGLE OF ACTIVATION OF THE
LOWER TRAPEZIUS MUSCLE IN THE FEMALE COLLEGE-AGED POPULATION
by
Kelvin Duc Lam
A project submitted in partial
fulfillment of the requirements for the degree of Doctor of Physical Therapy
in the Department of Physical Therapy College of Health and Human Services
California State University, Fresno May 2015
APPROVED
For the Department of Physical Therapy:
We, the undersigned, certify that the project of the following student meets the required standards of scholarship, format, and style of the university and the student's graduate degree program for the
awarding of the doctoral degree.
Kelvin Duc Lam Project Author
Jenna Sawdon-Bea Physical Therapy
Bhupinder Singh Physical Therapy
Stephanie D. Moore-Reed Kinesiology
For the University Graduate Committee:
AUTHORIZATION FOR REPRODUCTION OF DOCTORAL PROJECT
X I grant permission for the reproduction of this project in part or in its entirety without further authorization from me, on the
condition that the person or agency requesting reproduction absorbs the cost and provides proper acknowledgment of authorship.
Permission to reproduce this project in part or in its entirety must be obtained from me.
ACKNOWLEDGMENTS
I would like to acknowledge the assistance of Dr. Jenna Sawdon-Bea, Dr. Bupinder Singh, and Dr. Moore-Reed for guidance and support.
TABLE OF CONTENTS Page LIST OF TABLES ... vi INTRODUCTION ... 1 METHODS ... 4 Subjects ... 4 Instrumentation ... 4
Maximum Voluntary Isometric Contraction ... 5
Statistical Analyses ... 6 RESULTS ... 7 DISCUSSION ... 8 CONCLUSION ... 13 REFERENCES ... 14 TABLES ... 18 APPENDICES ... 24
APPENDIX A: STUDIED EXERCISES ... 25
LIST OF TABLES
Page
Table 1. PROCEDURES AND TESTING MATERIALS ... 19
Table 2. EXERCISE DESCRIPTION ... 20
Table 3. DUMBBELL WEIGHTS DISTRIBUTION ... 21
Table 4. LOWER TRAPEZIUS EXERCISES MEAN % MVIC, n = 27 ... 21
Table 5. % MVIC MAIN EFFECT FOR EXERCISE AND ANGLE ... 22
Table 6. LOWER TRAPEZIUS EXERCISE MEAN UT/LT RATIO, n = 27 ... 22
Table 7. UT/LT RATIO MAIN EFFECT FOR EXERCISE AND ANGLE ... 23
INTRODUCTION
One of the most common conditions treated by physical therapists is the shoulder and neck region musculoskeletal pain, which is associated with limited range of motion.1 In addition, descriptive research and laboratory controlled studies confirm that shoulder injuries have been reported as the most prevalent injury to occur in overhead athletes.2-6
The shoulder complex is considered one of the most mobile joints in the human body and enables the positioning of the arm almost anywhere in space.7,8 As a result of increased mobility of the shoulder, there is often an increase incidence of injury at the shoulder joint. The anatomical composition of the shoulder is critical in explaining the common pathologies that often result.
Numerous articles have correlated the scapulothoracic dysfunction with shoulder injuries and the role of the scapula pathogenesis.3,5,6,9-11 Scapulothoracic dysfunction is defined as alteration of the scapula in resting or dynamic position that changes the scapula muscles affecting the normal shoulder movements and function.5 A meta-analysis done by Timmons et al.12 reported that altered scapular orientation may lead to the development of rotator cuff pathology, specifically subacromial impingement syndrome and internal rotator cuff impingement.
Various studies have found that the contribution of excess upper trapezius activity reduced the lower trapezius (LT) and serratus anterior activity and correlates to decreased upward rotation and posterior tilting of the scapula during arm
elevation.3,5,11,13,14 Additionally, dysfunction at the shoulder complex is correlated with weakness of the trapezius muscles, thereby negatively impacting its crucial role in maintaining appropriate shoulder kinematics.15 Reinold et al.16 reported the function of the lower trapezius muscle plays an important role; it contributes to
2 2 posterior tilt and external rotation of the scapula during arm elevation, thus
decreases the risk for subacromial impingement.
With hopes of decreasing shoulder injuries, literature supports
strengthening exercises to address scapulothoracic muscle weakness, however, the effectiveness in activating these muscles across multiple exercises is mixed. 3,5,6,9,17-19
Descriptive laboratory studies have suggested that prone shoulder horizontal abduction with external rotation is an optimal exercise to activate the lower trapezius5,16,17,19 In addition, Kibler et al.9 reported that the lawnmower exercise activates the lower trapezius in larger amplitudes 30.5 + 19.2% and can be used to effectively strengthen the LT muscle in early stage of rehabilitation. Andersen et al.6 reported that one arm row can result in 39% maximum voluntary isometric contraction (% MVIC) at low intensity (Borg CR10 scale level 3) and 53% MVIC at high intensity (Borg CR10 level 8) and prone horizontal abduction 55% MVIC (low intensity) and 70% MVIC (high intensity), with both exercises predominately activating the lower trapezius over the upper trapezius (UT). Percent maximum voluntary isometric contraction is defined as a standardized methods and tools to measure muscular strength objectively.20 Although numerous studies have
investigated multiple scapular muscle exercises to target the lower trapezius (LT) activity5,6,9,18,19,21, none have determined the optimal activation of the LT at different angles, specifically in female college population. The purpose of this study is to investigate the peak percent maximum voluntary isometric contraction (% MVIC) of the LT in the following three exercises: shoulder horizontal
abduction with external rotation (HAER), one-arm bent over row (BOR), and lawnmower (LM), at three different angles (45°, 90°, 125°) in the female college-aged population. The second purpose of this study is to observe the UT) activity in relation to LT exercise at three different angle mentioned above. We hypothesize
3 3 that HAER performed at 125° will yield the highest percent maximum voluntary
METHODS Subjects
Thirty-two female volunteers signed up to participate in the study, however only 27 participants met the criteria. The mean age was 24.7 + 1.90 years, mean height was 1.65 + 0.8m, mean weight was 59.19 + 7.67kg and mean body mass index was 21.63 kg/m2 + 1.94. The inclusion criteria in the study were healthy females between ages of 18 to 28 years. Exclusion criteria included cervical spinal injury, history of shoulder pain due to trauma, fracture, dislocation, and surgery within the past year. Both inclusion and exclusion criteria were gathered and assessed with an intake form. Prior to participation, all subjects were required to read and sign the informed consent, intake form, and UCLA activity scale (see Appendix A). This study was approved by the Physical Therapy Department’s Committee for the Protection of Human Subjects and the Research Guidance Committee.
Instrumentation
Skin preparation was performed prior to electrode placement and EMG recording. Excessive hair was shaved as appropriate and alcohol pad was utilized to remove dead skin to decrease skin impedance (<10 kΩ). Electrode placement followed SENIAM recommendations which can be found at www.seniam.org. Bipolar surface electrodes (MVAP 1” x 1 7/8”, foam electrode with 2 snaps and 2 gel sites, 1 cm space between electrodes) were placed over the upper trapezius and lower trapezius muscles. The portable TeleMyo DTS receiver was connected to the laptop recording device. Two TeleMyo DTS sensors were attached on the participant’s skin near the surface electrodes with Noraxon adhesive tape. Two set of bipolar recording electrodes were connected to TeleMyo DTS wireless sensor
5 5 with the DTS EMG lead set (see Appendix A). The sampling rate was set at 1000
Hz. All raw myoelectric signals were preamplified with an overall gain of 1000. The common rejection ratio rate was set at 100 dB and signal to noise ratio <1 μV RMS baseline noise. The filter to produce a bandwidth was set at 10-1000 Hz.
Maximum Voluntary Isometric Contraction
Prior to determining the percent maximum voluntary isometric contraction (% MVIC) for the LT muscle, the rhomboid muscle was screened to ensure the EMG activity was solely a result of LT activity. Procedures to screen the rhomboid were performed in accordance to Smith et al.22 and Hislop and
Montgomery23. Manual muscle testing (MMT) was performed to determine MVIC specific to the LT muscle. The subject was positioned in prone with a belt strap across the mid gluteal and pelvic region to ensure safety and prevent subject from rolling over during the process. The subject’s arm was placed diagonally overhead in line with the LT fibers by using a goniometer set at 125° with the fulcrum at the acromion process, movement arm at the lateral epicondyle of the humerus, and the stabilizing arm placed parallel to the trunk. The researcher was positioned next to the participant’s testing arm and placed both hands and arms fully extended on top of each other at the distal part of the radius. A resistance was applied against
further elevation and was held for 3 seconds prior to overpowering the LT within 5 seconds. See Table 1 for further details for MMT positioning and procedures.
The exercise order was randomized through drawing by the researcher to prevent systematic error. Each participant performed three different exercises at three different angles (45°, 90°, and 125°). Participants were asked to perform 5 trials with a metronome set at 35 bpm to control the duration for each trial. Participants were given 30 seconds resting period upon completion of 1 exercise
6 6 and 2 minutes in between upon completion of 3 exercises regardless of angle.
Verbal encouragement was given to all participants. Table 2 demonstrates the exercises and the use of a goniometer and boney landmarks to determine the shoulder angle which was held during each exercise. Table 3 demonstrates the weight distribution based on the participant’s weight group. All participants were allowed up to 5 practice trials with the researcher guiding the movements to the angle of interest. The researcher readjusted the arm position if the participant was not in line of the intended angle. The participant was asked to repeat the exercise at the correct angle and EMG recording was recollected. The peak MVIC for each trial was used for data calculation.
Statistical Analyses
Statistical software IBM SPSS (version 20) was used for data analysis. An intraclass correlation coefficient (ICC) was carried out prior to the study to determine the test-retest reliability of electrode placement for the UT and LT. Descriptive statistics were calculated. A factorial 2 way analysis of variance (ANOVA) for repeated measures was used with the within-subjects factors consisting of “exercise” (3 levels) and “angle” (3 levels) for mean % MVIC and mean UT/LT ratio. Least significant difference (LSD) post hoc tests were
performed when appropriate. UT/LT ratio reference values were defined a priori. Ratios >1 demonstrate UT was more active than the LT while ratios <1 suggest LT was more active than UT.5 Additionally, a subcategory for ratios <1 was established to include 1.0 to 0.8 (moderate), 0.79 to 0.60 (good), and < 0.59 (excellent).5 Based on this classification, exercises at each angle were analyzed to determine the lowest UT/LT ratio. In determining significant difference, an alpha level was set at 0.05.
RESULTS
A pilot study was done on the electrode placement for the UT and LT test-retest ICC prior to EMG recordings. The results from 10 subjects indicate
reliability for LT (0.90) and UT (0.91).
Table 4 demonstrates the descriptive statistics of the mean % MVIC for the 3 exercises at 3 different angles. The repeated measures ANOVA for %MVIC revealed a significant main effect for % MVIC exercise (F(2,52) = 23.32, P < .001) and for angle (F(2,52) = 57.74, P < .001) (Table 5). Table 6 demonstrates the descriptive statistics of the mean UT/LT ratio for the 3 exercises at 3 different angles. The analysis for UT/LT ratio revealed a significant main effect for exercise (F(2,50) = 6.70, P < .05) and for angle (F(2,50) = 6.91, P < .05) (Table 7).
DISCUSSION
The primary purpose of this investigation was to observe the peak % MVIC for HAER, BOR, and LM exercises at 45°, 90°, 125°, specifically in the female college-aged population. The secondary purpose is to observe the UT activity in relation to LT exercise at three different angles mentioned above. The results partially support the primary hypothesis that the optimal exercise to activate the lower trapezius was HAER when performed with the shoulder in 125° of
abduction. Similarly, the results partially supported the secondary hypothesis in which HAER perform at 45° will yield the least UT/LT ratio.
A main effect for % MVIC was observed for exercise alone. This indicated that the HAER exercise was better at recruiting the LT muscle when compared to the BOR and LM exercises respectively; regardless of any angle that the exercise was performed at. Ekstrom et al.18 and Cools et al.5 reported high levels of EMG activity in the LT muscle when the shoulder was externally rotated with the subject in a prone position. Ekstrom et al.18 suggested the optimal exercise for activating the LT was in prone position with arm raise overhead in line with the LT fibers 97 + 16 % MVIC. Our investigation demonstrated similar result with HAER 95.72 + 10.80 % MVIC having the greatest LT activity. Additionally, HAER performed at 90° indicated 87.84 + 15.76 % MVIC had a similar result as the Ekstrom et al.18 study when performed in the same position 79 + 21 % MVIC. Although Ekstrom el al.18 did not report % MVIC at 45°, our study found HAER at 45° resulted a high LT activation 73.64% + 17.25 % MVIC (>60% MVIC).18,21
Similarly, a main effect for % MVIC was observed for exercise alone. Regardless of exercise, performing in shoulder abduction at 125° were found to be most effective in activating the lower trapezius muscle following 90° and 45°
9 9 respectively. Lim et al.24 reported the horizontal abduction with external rotation
in 16 healthy male subjects lower trapezius EMG activity at 120° demonstrated the highest activation (56.88 + 12.20 % MVIC) without weights when compared to 90°, 60°, and 30°. Various studies15,17-19,21,24 have reported that exercises
performed in line with the LT muscle fibers demonstrate strong muscular
recruitment. While our study findings indicated similar results, the data revealed that regardless of the exercise (HAER, BOR or LM), performing them at 125° yielded the greatest recruitment followed by 90° and 45°. However, there was no significant interaction for % MVIC for exercise x angle. This finding is clinically relevant as it provides information for a clinician when selecting an appropriate exercise to strengthening the lower trapezius muscle during rehabilitation.
A significant main effect for the mean exercise UT/LT ratios revealed that HAER 0.66 + 0.31 and BOR 0.67 + 0.27 had similar results. This indicated that UT activity is considered moderate while producing an optimal LT activity.
Whereas, LM 0.85 + 0.41 revealed a moderate findings suggesting that the UT/LT ratios was fairly moderate to high.
While HAER demonstrate the greatest % MVIC for LT activity, BOR exercise demonstrated the second highest LT activity. Rowing exercises have been recommended in various studies for strengthening the lower trapezius
muscles, but the positioning for the rowing exercise is not uniform 11,17,18 Moseley et al.17 reported 68 + 41 % MVIC for LT activity while Ekstrom et al.18 reported 45 + 17 % MVIC for the LT; both were performed in a prone position. Andersen et al.6, reported 39%-53% MVIC with 0.61 to 0.81 UT/LT ratio for one arm row at low and high intensity in the position that was similar to the BOR exercise at 45° (59.22% MVIC) with 0.67 UT/LT ratio. Surprisingly, our result indicated that the main effect for BOR exercise was at 74.44 + 13.13 with a moderate UT/LT ratio
10 10 0.67 + 0.27, suggesting strong muscular activity (>60% MVIC) with moderate
UT activity. This finding is clinically relevant because it provides clinicians an alternative exercise position to strengthen the LT while maintaining a high LT muscular activity with moderate UT activity.
The exercise that demonstrated the least % MVIC was the LM. This exercise is considered a multi-joint exercise that consists of hip/trunk extension, trunk rotation, and scapular retraction which activate the scapulothoracic muscles to stabilize the scapular during glenohumeral mobility.9 Our study found the LT activity at 45° was 52.10 + 17.15 % MVIC. In contrast, Kibler et al.9 reported a MVIC amount of 30.5 + 19.2 % MVIC. The overall main effect from our results for LM was 67.17 + 14.63 % MVIC with weight. The UT/LT ratios indicate moderate findings at 0.83 + 0.41, indicating a potential exercise of choice to strengthen LT muscle in the early and later stages of rehabilitation.9 However, the discrepancy between the results from our study and Kibler et al.9 could have been due to the angle difference, the use of weights, and differences in methods when performing the exercise.
Overall horizontal abduction, bent over row, and lawnmower are exercises that focus on scapular retraction which all had similarities in scapular motion control to provide stability during glenohumeral mobility.3,16,17,25 Performing these exercises at a 125° position placed the humerus in line with the muscle fibers thus increasing the activity of the lower trapezius15,18. However, as the angle decreases to 45°, the LT activity decreases due to the humerus not being in an optimal position, therefore reducing the angular force (moment) production.26
As indicated in our study, LM exercise demonstrated the least amount of mean % MVIC while HAER demonstrates the highest LT mean % MVIC. This result may due to the HAER performed in position that is against gravity with a
11 11 longer lever arm increasing the moment force being pressed upon the LT muscle
fibers.27,28 The LM exercise demonstrating the least % MVIC possibly due to the participant’s erect standing position. This upright posture placed the LT muscle in a gravity minimized position with the elbow in a flexed position, thus reducing the lever arm. As a result, there was less of a moment force generated; therefore decreasing the LT muscular activity.26,27 Moreover, BOR demonstrates a moderate activation of LT possibly due to the combination of being in a position that is going against gravity, with the lever arm shorter than HAER, therefore placing this exercise in between the HAER and LM exercise.26,27
Limitations that should be noted are the use of EMG during dynamic activity resulting in skin displacement, movement artifacts, EMG signals/noise, rate of contraction, and normalization methods.29,30 During exercise performance, a potential skin displacement may occur causing the surface electrode to be displaced into another position; thus increased the risk for cross-talk with
rhomboid muscle. However, due to the lower trapezius being a superficial muscle and the rhomboid muscle was screened out prior to data collection, we feel that this did not affect the EMG recording. The speed of contraction and the force production has been demonstrated to influence the EMG recording in which there is a relationship between velocity and force production.31 By utilizing the
metronome for all of the exercises, this reduced the likelihood for error during EMG recording. Systematic error is another potential interference in obtaining reliable EMG data. However, this was addressed with randomization through random drawing of exercise and angle to control for systematic error and improve accuracy. Goniometric measurement may contribute to error, but we feel that this had minimal affect as the intra-rater reliability for goniometric measurement has been demonstrated to be high with the standard error of measure from 4-7°. Our
12 12 EMG study consisted of data from healthy female college-aged population without
shoulder and/or spinal injury, and this considered as a clinical limitation and caution should be used when applying these results to individuals with shoulder and spinal pathology. The purpose of our research was primarily focused on the LT relative to UT muscular activity and optimal angle rather than examining the whole trapezius muscle. Further examination should consider looking at bilateral activation, as well as the role of the serratus anterior as an important scapular stabilizer.14,16,21
CONCLUSION
Overall, this investigation suggests that the optimal exercise to strengthen the LT muscle is horizontal abduction with external rotation when compared to bent over row and lawnmower exercises. Performing these exercises at a 125° results the highest activation across all exercises while exercising at a 45° results in the least amount of LT activity. However, for an individual who cannot abduct the shoulder to 125°, an alternative angle at 90° may produce moderately high LT activity while maintaining moderate UT muscle activity. Our results on the EMG activity from horizontal abduction with external rotation, bent over row, and lawnmower demonstrated overall high LT muscular activity with relatively good to moderate UT activity. These findings may provide options for clinicians when treating a client with of scapular muscle weakness.
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19 19 Table 1. PROCEDURES AND TESTING MATERIALS
Surface Electrode and Receiver
Placement Manual Muscle Test
NORAXON TeleMyo DTS NORAXON TeleMyo DTS Sensors MVAP 1” x 1 7/8”, foam electrode
20 20
Table 2. EXERCISE DESCRIPTION HORIZONTAL
ABDUCTION WITH EXTERNAL ROTATION
HA 45 HA 90 HA 125
Bent Over Row
21 21
Table 3. DUMBBELL WEIGHTS DISTRIBUTION
Studied Exercise 40-49 kg 50-59 kg 60-69 kg 70-85 kg
HAER 1.81 2.27 2.72 3.18
BOR 1.81 2.27 2.72 3.18
LM 1.81 2.27 2.72 3.18
Abbreviation: HAER, Horizontal Abduction with External Rotation; BOR, Bent over row; LM, Lawnmower
Abbreviation: % MVIC: Percent Maximum Isometric Voluntary Contraction, HAER: Horizontal Abduction with External Rotation, BOR: Bent over row, LM: Lawnmower
Table 4. LOWER TRAPEZIUS EXERCISES MEAN % MVIC, n = 27 Exercises % MVIC + SD Mean + SD 45° 90° 125° HAER 73.64 + 17.25 87.84 + 15.76 95.10 + 10.80 85.53 + 11.78 BOR 59.22 + 20.16 77.96 + 16.76 86.14 + 13.54 74.44 + 13.13 LM 52.10 + 17.15 70.21 + 20.36 79.21 + 20.13 67.17 + 14.63
22 22
Table 5. % MVIC MAIN EFFECT FOR EXERCISE AND ANGLE
Exercise Mean + SD Angle Mean + SD
HAER 85.53 + 11.78 45° 61.65 + 11.78
BOR 74.44 + 13.13 90° 78.67 + 14.51
LM 67.17 + 14.63 125° 86.82 + 11.50
Abbreviation: HAER, Horizontal Abduction with External Rotation; BOR, Bent over row; LM, Lawnmower
Table 6. LOWER TRAPEZIUS EXERCISE MEAN UT/LT RATIO, n = 27 Exercises
UT/LT Ratio + SD Mean +
SD
45° 90° 125°
HAER 0.53 + 0.27 0.67 + .36 0.77 + .38 85.53 + 0.31 BOR 0.62 + 0.28 0.68 + .31 0.71 + .30 74.44 + 0.27 LM 0.80 + 0.41 0.88 + .48 0.88 + .44 67.17 + 0.41 Abbreviation: % MVIC: Percent Maximum Isometric Voluntary Contraction, HAER: Horizontal Abduction with External Rotation, BOR: Bent over row, LM: Lawnmower
23 23
Table 7. UT/LT RATIO MAIN EFFECT FOR EXERCISE AND ANGLE
Exercise Mean + SD Angle Mean + SD
HAER 0.66 + 0.31 45° 0.65 + 0.27
BOR 0.67 + 0.27 90° 0.74 + 0.31
LM 0.85 + 0.41 125° 0.79 + 0.33
Abbreviation: HAER, Horizontal Abduction with External Rotation; BOR, Bent over row; LM, Lawnmower
26 26 EXERCISE DESCRIPTION
Exercise Name Description
Prone horizontal abduction with external rotation
The subject in prone position with the shoulder in resting position at 90° forward flexed. The subject performs horizontal abduction on the test extremity with shoulder external rotation toward the ceiling.
Bent over row
The subject in standing position, bends the torso forward to approximate 30 degrees from horizontal with one knee on the bench with the opposite foot on the ground. The subject pulls the weight toward the ipsilateral lower rib, while the contralateral arm and torso are maintained in extended position.
Lawnmower
The subject is positioned with the trunk slightly flexed and rotated to the contralateral side of the test extremity. The hand of the test extremity start at the level of the contralateral patella then rotate the trunk toward the test extremity. Upon extending the hip and trunk to a vertical position, the test extremity retract the scapula to place the elbow in the back to 90° while simultaneously retracts the scapula with shoulder abducted.
28 28
UCLA Activity Score
Check one box that best describes current activity level.
1. Wholly Inactive, dependent on others, and can not leave residence
2. Mostly inactive or restricted to minimum activities of daily living
3. Sometimes participates in mild activities, such as walking, limited housework and limited shopping
4. Regularly participates in mild activities
5. Sometimes participates in moderate activities such as swimming or could do unlimited house work or shopping
6. Regularly participates in moderate activities
7. Regularly participates in active events such as bicycling
8. Regularly participates in active events, such as golf or bowling
9. Sometimes participates in impact sports such as jogging, tennis, skiing, acrobatics, ballet, heavy labor or backpacking
Fresno State
Non-Exclusive Distribution License
(to archive your thesis/dissertation electronically via the library’s eCollections database)
By submitting this license, you (the author or copyright holder) grant to Fresno State Digital Scholar the non-exclusive right to reproduce, translate (as defined in the next paragraph), and/or distribute your submission (including the abstract) worldwide in print and electronic format and in any medium, including but not limited to audio or video.
You agree that Fresno State may, without changing the content, translate the submission to any medium or format for the purpose of preservation.
You also agree that the submission is your original work, and that you have the right to grant the rights contained in this license. You also represent that your submission does not, to the best of your knowledge, infringe upon anyone’s copyright.
If the submission reproduces material for which you do not hold copyright and that would not be considered fair use outside the copyright law, you represent that you have obtained the
unrestricted permission of the copyright owner to grant Fresno State the rights required by this license, and that such third-party material is clearly identified and acknowledged within the text or content of the submission.
If the submission is based upon work that has been sponsored or supported by an agency or organization other than Fresno State, you represent that you have fulfilled any right of review or other obligations required by such contract or agreement.
Fresno State will clearly identify your name as the author or owner of the submission and will not make any alteration, other than as allowed by this license, to your submission. By typing your
name and date in the fields below, you indicate your agreement to the terms of this distribution license.
Embargo options (fill box with an X).
Make my thesis or dissertation available to eCollections immediately upon submission.
Embargo my thesis or dissertation for a period of 2 years from date of graduation. Embargo my thesis or dissertation for a period of 5 years from date of graduation.
Type full name as it appears on submission
Date
Kelvin Lam
May 2, 2015
