Shoulder Rehabilitation: Applying EMG Studies to Your Practice Session 102 Tim L. Uhl PhD ATC PT FNATA email: tluhl2@uky.edu Department of Rehabilitation Sciences College of Health Sciences, University of Kentucky Background

• Rehabilitation exercises are often based on EMG findings

• Understanding how theses studies are performed is often unclear

• As a young clinician selecting proper exercise progression seems to be a lot of art

• Our profession is asking clinicians to provide scientific evidence on which they base their exercise selection decisions

Objectives • Describe capabilities and limitation of EMG data • Review physiology of healing as it applies to prescribing therapeutic exercises • Describe rehabilitation exercise progression based on EMG activity Electromyography • The recording and analysis of myoelectrical signals derived from motor unit activity • Motor Unit

– Nerve cell body in the spinal cord – The motor nerve (axillary) – The muscle fibers that the nerve innervates

When a Muscle Contracts • Action potential travels down motor unit to end plate near the fibers • ACh causes breakdown of membrane to produce motor action

potential • Potential created across sarcolemma What does EMG measure? Action Potential Propagation • The recording electrodes detect the relative voltage difference

between the two electrodes as the action potential propagates along the muscle fibers

–

This is EMG • Electrical activity of Upper and Lower Trapezius during arm

elevation • Electrodes detect the electrical signal from muscular contraction

produced by the nerve innervating tissue • Computer stores the data EMG is a Sinusoidal Wave Considerations for Collecting and Using EMG data • Electrode

– Type – Size – Placement

• Skin preparation to diminish impedance • Electrode location • Data analysis parameters (processing) • Kinematic data collected simultaneous with EMG Types of Electrodes • Indwelling Electrode

– Fine wire • Commonly nickel-chromium with nylon or Teflon coating (50μ) • 25 -27 gauge needle • Bend ends to prevent backing out • Indwelling EMG electrodes measure energy from a few motor units (millivolts or microvolts) Surface Electrodes • Electrode made of Ag/AgCL

– conductive medium • Electrode geometry

– disc, bar, rectangular – Size ~10mm

• Inter-electrode distance – 10-40mm most common 20mm – Too far apart pick up other muscle activity

• Surface EMG records energy from multiple motor units (microvolt) Volume Conduction • Motor units closes to electrodes have most effect on electrical

recording • Skin, fat, fascia act as low pass filter Skin preparation • Impedance = Opposition to the flow of electrons or current flow in alternating currents • To diminish impedance: Remove hair, skin, oils • Procedure

– Shave hair – Debride dead skin with sand paper – Clean with alcohol

Electrode Placement

• Orientation of electrodes and location on muscle effects signal response

• Ideal location between mid portion and musculotendinous junction Electrode Placement • Consistent position enhances reliability

• Use of bony landmarks and percentage of distance from landmarks8, 34, 44 Bipolar Electrode Configuration Critical Differential amplification • Records relative voltage difference between the electrodes as the AP changes underneath the surface

electrodes • Voltage that is common to each electrode is eliminated (ground electrode) • Orient electrodes parallel to muscle • Works because electrical signal reaches electrodes at two different times Application Recommendations11, 17

• Bipolar surface electrodes with detection surface of 1.0cm, spaced 1-2cm apart.

• Placed between motor end plate and tendon oriented parallel to muscle fibers

• Parallel to muscle orientation

• Minimize input impedance with clean skin Gain

• Multiplier to amplify the signal

• 2000 often used for surface electrodes

• Example

• the original signal is .000063V or 63microV

• If gain at 2000

• 2000 x .000063v =.126V or 126millivolts EMG Signal Processing • Various procedures used depending on the question • To determine onset • Rectify signal • Smoothing

– Low pass filters (allow frequencies under set frequency pass) – High pass filters – Band pass filters (allow frequencies between boundaries pass)

• Most of the signal for Surface EMG is in 5-500Hz • Indwelling ranges 10 - 1500Hz EMG Signal Processing19

• To determine onset a criteria has to be set to determine when muscle is on or off

• 3 standard deviations above resting amplitude

• Muscular activity remains above that level for 25-50msecs Onset of Muscular Activity • Upper Trapezius on 225ms prior to arm elevation • Lower Trapezius turns on 343ms after arm elevation

Utilization of EMG in Rehabilitation and Research

• Initiation of muscle activation (Onset)

• Duration of muscle activation

• Reflex latencies – time it takes muscle to respond to a disturbance

• Amount of muscle activation (Amplitude)

• Measure of fatigue occurring in a muscle Do Athletes have Quicker Reaction Times than Non-Athletes? • Reflex latency and onset • (Muscle latency) from pushing the arm into internal rotation • We measured how quickly does the supraspinatus, infraspinatus, and posterior deltoid turn on Measure of EMG Amplitude

• To determine how much muscular activity for a particular exercise

• EMG activity is translated from Volts to percentage of muscle activity.43 – MVC – maximal voluntary contraction – RVC – reference voluntary contraction

Relative Amount of Muscular Activity • Normalization of EMG signal to an event or to a specific task • Allow for comparison across individuals for the same activity Normalization allows for Comparison • Assist in comparison of EMG signals

– Across muscle – Between subjects – Between exercises

• 100% isometric contraction (MVIC) – Most commonly used – Need to perform for 3-5 sec duration – Multiple repetitions with at least 30-90 sec rest

• The highest time interval (one second) of EMG signal is considered 100% MVIC • EMG data is expressed as a % MVIC

Normalization • Often manual muscle test positions are used24 • Specific positions identified for rotator cuff musculature22 EMG Amplitude during Elevation • Divide activity of event by MVIC to get percentage • Using RMS amplitude • Upper Trapezius = 39% • Lower Trapezius = 23%

EMG Amplitude during Elevation • Divide activity of event by MVIC to get percentage at different arcs of motion • Using Linear Envelop (IEMG) • Upper Trapezius =

– 0-20 = 40% – 20-40 = 36%

• Lower Trapezius = – 0-20 = 18% – 20-40 = 13%

Muscle Performance Question

• Research questions related to EMG amplitude allows us to identify what exercise activates particular muscles to a greater extent relative to the other – Does OPEN or CLOSED chain exercises activate the supraspinatus more?

• To answer this question need to evaluate relative muscle activity

• Exercise Protocol • Open vs Closed Chain

– Vertical position – Diagonal position (45o) – Horizontal position

• Sphygmomanometer: Used to monitor load Open vs Closed All 3 Positions Combined EMG Amplitude Categorization

• 0 – 20% Low activity – 0 – 5% Minimal EMG activity (background noise)35

• 21 – 40% Moderate activity

• 41 – 60% High activity

• 61% + Very High activity12

Limitations of EMG • Possibility of “cross-talk”

– Surface EMG activity is not always pure – Use small electrodes and small interelectrode distance

• Not a measure of force or strength – Moderate correlation in an isometric conditions20

• During dynamic activities muscles move under skin motor units • Limited number of muscles to test

Limitations of EMG • Noise or Artifact • Moving / loose electrodes • Cable connections • Electrocardiogram (heart beat signal) • Electrical fields Objective 2

• Review physiology of healing as it applies to prescribing therapeutic exercises Tendon Anatomy • Interposed between bone and muscle to transmit and absorb force • Specialize insertions • Viscoelastic structure that responds to load and rate of loading Tendon Properties21 • Tolerates tremendous tensile stresses due to collagen construct

– 50-100 N/mm2 – 1cm2 can support ~500kg

• Has good flexibility due to elastic fibers – Ruptures at ~8% elongation

• Does not tolerate compression and shear forces as well Tendon Attachment • Myotendinous junction

– Muscle force is transmitted to tendon – Finger like processes to increase contact area thereby reducing force per area

• Osteotendinous junction – Transitioning through fibrocartilage provides a buffer for the tensile loads and the various load

orientations Tendon Attachment • Direct

– Bone – Mineralized fibrocartilage – Unmineralized fibrocartilage – Tendon

• Indirect – Collagen fibers blend with periosteum and is anchored to bone via Sharpey’s fibers

Rotator Cuff Tendon Rupture29

• Not typically traumatic

• Degenerative overuse mechanism most common

• Combination of compression and eccentric overload

Tendon Healing21 Extrinsic • Peritendous structures infiltrate injured tendon provide blood supply and form granulation tissue • Reliant on adhesions to heal • Immobilization facilitates this type of healing Intrinsic • Repair of tendon derives from the epitendon and endotendon of the injured tendon • Dependent on preservation of microcirculation & sheath, good suturing, intermittent motion Time Frame for Tendon Healing • Inflammatory phase 0-3 days • Proliferative phase initiates in 1st week with fibroblasts increasing over the next 4 wks • Collagen maturing over several months • 4 - 6 months see maturation of repair Inflammatory Stage • Platlets start clot formation with fibrin & fibronectin • Chemical mediators attract WBC • Histamine, Bradykinin increases vascular permeability

– Fxn: to stop bleeding and debride area Supraspinatus Tendon2 • Normal Proliferative Phase • 4 weeks into healing see new bone forming decreased ECM and vascularity and sporadic connections to

bone • 8 weeks post surgery see cellular proliferation Remodeling Phase • Reduction in cellular activity • Syntheis of type I collagen • ECM less watery • Collagen fibers align along tensile forces • Fibroblasts revert less active fibrocytes (tenocytes)

– Fxn: Organization of final structure Biomechanical Properties of Rotator Cuff Tendon

• Maximal active force generated across supraspinatus has been estimated to be 302N = 68lbs Maximal Load to Failure of Repaired Rotator Cuff

• Comparison of simple vs. mattress suture repair directly to bone – Simple 190 N – Mattress 136N

• ~ 50% of normal strength Cyclic Loading 4

• Methodology that replicates physiological loading of a rotator cuff tendon • Intact human cadaver loaded with 180N at 33mm/s tolerates 3500 cycles no failure • Transosseous fixation failed at 188 (5%) cycles

• Suture anchor fixation failed at 285 (8%) cycles – < 45yo failed at 478 cycles – > 45yo failed at 91 cycles

• Implication: More repetitions is not necessarily better Biomechanical Properties of Healing Tendon15

• Tendon maximal strength ranges from 50 – 150MPa • Rat maximal tensile load =25 + 9 MPa 5

– 6wks = 8% – 12 wks = 12% – repaired supraspinatus post-op does not approach intact values

Biomechanical Properties of Healing Tendon28

• Sheep model: At 26 weeks of healing revealed return to maximal loads to failure equal to control limb

– Control 2500 + 101N – Immobilized for 6 weeks 2954 + 242N

– Non-immobilized 2572 + 168N Rehabilitation Implications15 • Tendon Response to Remobilization • Gradual return of biochemical and biomechanical

properties • Early controlled motion prevents adhesion and facilitates

healing Tendon Response to Inactivity • Immobilization reduces contact area between muscle

and tendon • Reduces sulfate glycosaminglycan “glue” of the myotendinous junction Immobilization Positioning • Hypovasularity of supraspinatus with arm at side36 • Adduction increases stress to the rotator cuff below 30°16 • EMG activity present in immobilizer39 • Caution for certain activities to protect of rotator cuff

– Bimanual tasks (biceps) – Pulling open door (Infraspinatus) – Fast forward reaching (deltoid)

Immobilization Effect on Healing40 • 65 rats repaired supraspinatus

– 25 immobilized in cast – 20 cage activity – 20 exercise – 1 wk post op- treadmill exercise (1 hr/day 5 x wk) – 11 control (no surgery)

• Results – Histological – Organizational: IM> CA & EX groups

– Biomechanical: (load to failure) all groups equal less than control – Viscoelastic properties: IM> CA & EX groups

Rehabilitation Implications

• First 3- 6 wks loads across the tendon have to be minimal • Gradual introduction of stresses during the maturation process • Pain may not be a guide due to new arthroscopic techniques

EMG Application to Rehabilitation • Objective 3: Describe rehabilitation exercise progression based on EMG activity • EMG is often used to determine which muscle is activated and to what degree (amplitude) during an

exercise3, 32, 41

Exercise Continuum Acute Phase Rehabilitation • Initiate ROM within pain tolerance and physiological healing restraints

– prevent substitution patterns • What exercises meet these goals? Muscle of Interest • Supraspinatus • Infraspinatus • Subscapularis • Serratus Anterior • Upper Trapezius • Lower Trapezius EMG Categorization12, 30

• 0 – 20% Low activity – 0 – 5% Minimal

EMG activity (background noise)35

• 21 – 40% Moderate activity

• 41 – 60% High activity

• 61% + Very High activity

PROM Exercises • Performed by

another • Performed by patient • Using stable surface PROM = Low Demand (>10%)

SupinePROM

forwardbow

Supraspinatus

Infraspinatus

Deltoid

Upper Trapezius

Lower Trapezius

Serratus Anterior

5

22

22

02

3

2

45

10

20

40EMG Activity (% MVIC)

60

80

100

Supraspinatus Infraspinatus Deltoid Upper Trapezius Lower Trapezius Serratus Anterior

AAROM Exercises • Critical period to avoid abnormal movement patterns or substitution patterns • Various assistive devices (Pulley, Stick, Wall) to minimize loads on healing tissue • Facilitates muscle activation and dynamic muscular control of the joint • Caution using long lever arms may be too much demand for recovering tissues Gravity Minimized AAROM Exercises • Use of water provides buoyancy decreases load on musculature23

– Slow motion low demand on muscles <10% – Fast motion moderate demand 20 – 40%

• Facilitates proximal trunk control • Wound considerations Movable Boundary No Load27 • Exercises that allow hand to move with support but minimally load arm • Unloading the weight of arm Sidelying Elevation AAROM • Unloading through a greater range of motion

– Arm supported – Horizontal plane

• Are all AAROM exercises basically the same? AAROM Exercises (Rotator Cuff)

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Supraspinatus

Subscapularis

Infraspinatus

Deltoid

172523

22

77

271110

21

118

74

427

97

11

2

17

109

97

54

32

2

0

20

40

60

80

100

EMG Activity (% MVIC)

Supraspinatus Subscapularis Infraspinatus Deltoid

AAROM Exercises (Scapular Muscles)

Upper Trapezius Lower Trapezius Serratus Anterior

0

20

40

60

80

100

EMG Activity (% MVIC)1817

121310 11611 9

9

AAROM = Arm Supported (~10%)

1. Gravity Minimized 2. Assisted Elevation 3. Unassisted Elevation

Sub-acute Phase Goals (6-12 wks) • Intermediary exercises • Re-establish coordinated UE

movement • Enhance strength • Loads on muscle critical

– Resistance – Speed – Lever arm

• Increase Endurance

0.00

1.06

2.12

3.18

4.24

5.30

6.36

7.42

8.48

9.54

10.60

11.66

12.72

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12311311 4

Upper Trapezius

Lower Trapezius

Serratus Anterior

11 51

18 11

2

RROM Varies According to Load (20 - 50%) Scapular Stabilization Exercises in Sling • EMG activity for subscapularis was moderate to high (30 – 70% MVC) • All other cuff and deltoid musculature low <20% MVC • Addition of step with exercise slightly increased EMG activity <10% • Lawnmower exercise keeping elbow low activated Serratus Anterior to very high levels > 80% while

other muscles remain <20% • Lawnmower exercises are safe in early phases of shoulder rehab except for subscapularis repairs38 Incorporating Scapular Stabilization Exercises without Sling 25 • Low Row and Inferior Glide

– 20+20% for LT and SA – UT <10%

• Lawnmower & Robbery – 20-40% for all scapular musculature

• These exercises are appropriate for intermediate phase scapular strengthening What about Closed Chain? • Fixed Boundary Axial Load • Greater joint congruency thereby decreasing shear forces • Facilitates motor control • EMG activity correlated to load R2 = .95 Muscular Demands with Common CKC Exercises 42 Prayer Quadriped Tripod Pointer Push up Push up elevated One hand push up Closed Chain Exercises

• Limited research in this area

• One arm position biases the infraspinatus & posterior deltoid

• Low load activities (<20% BW) facilitate co-activation Elastic Resistance Exercises33

• Rubber tubing for shoulder exercises • Developed for throwing athletes (on-field) • Identified 7 exercises that moderately activated primary muscle involved in throwing*

Elastic Resistance Exercises

Ant. Delt. Mid. Delt.Low. Trap. Serr. Ant.

Sub- scap. Supra. Infra.

mn sd mn sd mn sd mn sd mn sd mn sd mn sd Throwing Acceleration* 27 20 22 12 53 46 55 35 93 51 36 32 33 22Throwing Deceleration* 29 16 44 16 63 42 48 32 69 48 64 32 45 21ER at 0 6 6 8 7 48 25 18 19 72 55 20 13 46 20ER at 90* 22 11 50 21 88 51 66 39 57 50 50 21 51 30IR at 0 6 6 40 3 44 30 21 14 74 47 10 6 32 51IR at 90 28 18 41 21 54 39 54 32 71 43 41 30 24 21Shoulder Extension* 19 15 27 16 53 40 30 21 97 55 29 21 50 57Shoulder Flexion* 60 41 32 14 49 35 67 37 99 37 42 22 47 34Low Scapular Rows* 19 13 34 23 44 32 22 14 69 50 46 38 29 16Scapular Punches* 45 36 36 24 32 32 67 45 69 47 46 31 35 17High Scapular Rows 31 25 34 17 51 34 38 26 74 53 42 28 31 15Middle Scapular Rows 18 10 26 16 38 27 24 20 81 65 40 26 27 16 Emphasize Shoulder Endurance • Shoulder fatigue increase total translation of humerus 2.5mm6 • Emphasize high reps, good technique not heavy weights Endurance Considerations31 • Deltoid muscle fatigues at a faster rate than scapular muscle during prolonged elevation activities

– Upper Trap – Serratus Anterior – Lower Trap

• Median power spectral analysis Strengthening Progressions

• Progressions are muscular specific – Scapular Musculature9, 13, 14, 32 – Rotator cuff3, 10, 33, 37, 41

Subscapularis Progression

0

20

40

60

80

100

120

140

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Abductio

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IR lo

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Flexi

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IR a

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Serratus Progression9

• Least to most challenging based on average amplitude • Shoulder Extension= 5% (+ 3) • Press-up= 32% (+ 28) • Forward Punch= 34% (+ 15) • Scaption= 38% (+10) • Knee Push-up Plus= 40% (+ 15) • Serratus anterior Punch= 44% (+ 12) • Dynamic Hug= 50% (+ 15) • Push-up Plus = 58% (+ 17) Serratus Anterior Exercises (%MVIC) Exercise Mosely ’92 Ekstrom ‘03 Flexion 96 + 45 NT Abduction 96 + 53 NT

Scaption > 120o 91 + 52 96 + 24

Diag Flex/ Horiz Add/ Ext. Rot. NT 100 + 24 Military Press 82 + 36 NT Unilateral shoulder press supine w/plus

NT 62 + 19

Push up w/plus 80 + 38 NT Push up w/ hands wide 57 + 36 NT Bilateral scapular protract. NT 57 + 22 Lower Fibers of Serratus Anterior • Protraction focuses on upper fibers • Elevation above 120 deg is needed to address lower fibers of Serratus Ant. • Diagonal Flexion / Adduction / Ext. Rot.

Scapular Core Exercises

Upper Trapezius Lower Trapezius Serratus Anterior

96

82

0

20

40

60

80

100

EMG Activity (% MVIC)

96

Upper Trapezius Exercises (%MVIC) Exercise Mosely ’92 Ekstrom ‘03 Rowing 112 + 89 63 + 17 Shrug NR 119 + 23

Scaption > 120o 54 + 16 79 + 19

Prone Horiz. Abd w/ER 75 + 27 66 + 18

Prone Flex at 135o NT 79 + 18

Prone Horiz. Abd (neutral) 62 + 53 NT Diag Flex/ Horiz Add/ Ext. Rot. NT 66 + 10 Middle Trapezius Exercises (%MVIC) Exercise Mosely ’92 Ekstrom ‘03 Prone Horiz. Abd (neutral) 108 + 63 NT

Prone Flex at 135o NT 101 + 32

Prone Horiz. Abd w/ER 96 + 73 87 + 20 Rowing 59 + 51 79 + 23 Shrug NR 53 + 23

Scaption > 120o 62 + 53 49 + 16

Prone Extension 77 + 49 NT

Prone Ext. Rot @ 90o NT 45 + 36

Pro

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Sca

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PH

A 9

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92 68

Upper Trapezius

Lower Trapezius

Serratus Anterior

74

9

5760

60

79

6452

66

54

20

Lower Trapezius Exercises (%MVIC) Exercise Mosely ’92 Ekstrom ‘03

Prone Flex at 135o NT 97 + 16

Prone Ext Rot @ 90o NR 79 + 21

Abduction 68 + 53 NT Prone Horiz. Abd w/ER 63 + 41 74 + 21 Rowing 67+ 50 45 + 17

Scaption > 120o 60 + 22 61 + 19

Prone Horiz. Abd (neutral) 56 + 24 NT Rotator Cuff Core Exercises

Pro

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Sca

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R

Flex

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PH

A 9

0° E

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capt

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Supraspinatus

Subscapularis

Infraspinatus

Deltoid

647283

73

72

74

79

66

60

80505662

52

80

74

70

67

64

500

20

40

60

80

100

EMG Activity (% MVIC)

Supraspinatus Subscapularis Infraspinatus Deltoid

Advanced Phase Goals

• Progress to dynamic ballistic activities

• Return to work/sport specific tasks

• Normalize neuromuscular control Plyometrics7 • Overhead plyometric simulate and prepare body to return throwing activities Baseball Throwing

0

25

50

Early Cocking Late Cocking Acceleration FollowThrough

Phases of Throwing

75

100

125

150

175

200

%M

VIC

Infraspinatus

Supraspinatus

SubscapularisDeltoid Serratus Anterior

Trapezius Football Throwing

0

10

20

30

40

50

60

70

80

90

100

Early Cocking Late Cocking Acceleration Follow Through

Phases of Throwing

%M

VIC

Infraspinatus

Supraspinatus Subscapularis

Deltoid

Conclusion

• EMG studies can help you select appropriate exercise for your patient • There are often multiple variations to activate the muscle

– Think along a continuum of exercises • Using small steps of progression can keep your patient motivated • Design your program based on tissue physiology, available evidence, and your clinical judgement “The whole of science is nothing more than a refinement of everyday thinking.”

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Appendix of exercises and EMG data Acute Phase Exercises graded by (%MVIC + S.D.) Exercise Deltoid Supra-

spinatusUp.

Trap. Ser. Ant.

Low. Trap.

Supine PROM 3 + 1 1 + 6 1 + 2 2 + 2 2 + 2

Forward Bow 2 + 1 5 + 6 2 + 3 5 + 4 2 + 2

Sidelying Elevation

10 + 6 2 + 6 2 + 3 11 + 7 8 + 5

Towel Slides 12 + 7 7 + 7 4 + 3 7 + 4 1 + 1

Supine Press-up 1#

11 + 4 3 + 7 1 +3 16 + 8 1 + 1

T-Bar 24 + 9 9 + 9 9 + 8 17 + 6 10 + 10

N.A. = Not available

Sub-acute Phase Exercises graded by (%MVIC + S.D.) Exercise Deltoid Supra-

spinatusUp.

Trap. Ser. Ant. Low.

Trap.

Low Row25 42 + 23 N. A. 10 + 8 28 + 21 15 + 12

Inferior25 Glide

9 + 6 N. A. 8+ 6 23 + 19 19 + 26

Shrugs with elastic tubing18

N.A.

PK 44 + 25 AVG

10 + 6

PK 53 + 29

AVG 13 + 8

PK 31 + 24

AVG 5 + 4

N.A.

Lawnmower25

16 + 10 N.A. 22 + 16 26 + 21

27 + 21

Robbery25 14 + 9 N.A. 32 + 17 21 + 17 27 + 21

Rows with elastic tubing9, 18

N.A

PK39 + 16

AVG9 + 2

PK 34 + 23

AVG 9 + 6

PK10 + 6

AVG5 + 4

N.A.

Exercise Deltoid Supra-spinatus

Up. Trap.

Ser. Ant. Low. Trap.

Wedge Press-up

20 + 9 8 + 11 11 + 11 17 + 8 2 + 1

Ball Rolls 25 + 8 11 + 10 9 + 3 21 + 7 5 + 4

Ipsilateral Step- up

21 + 7 22 + 20 21 + 8 15 + 5 13 + 6

Active Elevation

32 + 8 19 + 12 19 + 9 23 + 7 19 + 8

Standing Press-up

30 + 11 30 + 17 24 + 8 29 + 13 9 + 5

Forward Punch18

PK 39 + 23 AVG

9 + 4

PK 48 + 83 AVG

8 + 3

N.A.

PK 49 + 14 AVG

10 + 3

N.A.

N.A. = Not available PK = peak amplitude during phase AVG = average amplitude during phase

Functional Phase Exercises graded by (%MVIC + S.D.) Exercise Deltoid Supra-

spinatusUp.

Trap. Ser. Ant. Low.

Trap.

Scaption > 12014, 41

72 + 13 64 + 28 79 + 19 96 + 24 61 + 19

Scaption < 801, 14

91 + 26 82 + 27 72 + 19 62 + 18 50 + 21

Unilateral Rows14, 41

72 + 20 N.A. 63 + 17 14 + 6 45 + 17

Prone Flexion @ 135 ABD14

N.A. N.A. 79 + 18 43 + 17 97 + 16

Diag Flex/ Horiz Add/ Ext. Rot.14

N.A. N.A. 66 + 10 100 + 24 39 + 15

Military Press14, 41

72 + 24 56 + 48 64 + 26 82 + 36 N.A.

Exercise Deltoid Supra-spinatus

Up. Trap.

Ser. Ant. Low. Trap.

Unilateral shoulder press supine w/plus14

N.A N.A 7+ 3 62 + 19 11 + 5

Push up w/plus26 N.A. N.A 50 140 30

Prone Horizontal ABD3, 14

79 + 20

78 + N.A.

66+ 18 9 + 3 74 + 21

Prone ER @ 903, 14

N.A.

50 + N.A.

20+ 18

57 + 22 79 + 21

N.A. = Not available