• The Introduction and Application of Kinesiology, Biomechanics, and Assessment
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  • Chapter 7

    Shoulder Joint Complex

    Learning Outcomes: Students will be able to:

    1. Describe the musculoskeletal anatomy of the shoulder girdle, shoulder joint, and associated connective tissues that support these joints.
    2. Articulate the functional design of each shoulder girdle and shoulder joint and the osteokinematic and arthrokinematic movements possible at each joint.
    3. Describe the origin, insertion, actions, and nerve innervation of the muscles that act on the joints of the shoulder joint complex.
    4. Identify the characteristics of the different stages of development of musculoskeletal deformities and associate them with various conditions discussed in class.
    5. Identify the general guidelines for muscle testing & therapeutic exercise and be able to apply this knowledge in problem solving of case studies and in determining the best way to “isolate” muscles for the purpose of strengthening and stretching.
    6. Identify how to strengthen and stretch each of the muscles or muscle groups for performance enhancement and anatomical deviation (i.e. Upper Crossed Syndrome) intervention.

    The joints of the shoulder girdle and shoulder form the shoulder joint complex. This complex consists of the humerus, scapula, clavicle, sternum, as well as the sternoclavicular, acromioclavicular, and glenohumeral joints. Most movements of the arm at the glenohumeral joint (shoulder) requires a coordinated movement with the shoulder girdle (scapula and clavicle with associated joints), “moving as a unit”. This coupling of shoulder girdle movement with shoulder joint movement is called scapulohumeral rhythm.

    Specifically, the shoulder girdle consists of the manubrium, scapula, and clavicle, as well as the sternoclavicular (SC) and the acromioclavicular (AC) joints. The scapulothoracic articulation (STA) is not a true joint but is frequently used to simplify movement analysis of the shoulder girdle.

    Sternoclavicular Joint (SC) (complex saddle joint - triaxial)

    • Closed-Packed Position: Shoulder abducted 180º,     Open-Packed Position: Arm resting by side

    1. Articular Disc: serves to 1) improve joint congruency and 2) to absorb shock. Makes joint function as a sellar joint.

    1. Anterior & Posterior Sternoclavicular ligaments: reinforce the joint capsule anteriorly and posteriorly, limiting anterior, posterior and upward displacement of the clavicle respectively.

    1. Interclavicular ligament: connects the sternal ends of both clavicles. Crosess the SC joints superiorly and helps to prevent superior displacement of the clavicle.

    1. Costoclavicular ligament: attaches the costal cartilage of the 1st rib to the inferomedial surface of the clavicle.  Prevents superior displacement of the sternal end of the clavicle.

    Arthrokinematic Motion at the Sternoclavicular Joint

    Sternoclavicular Joint Range of Motion

    • During scapular elevation (frontal plane movement) there is a superior roll of the clavicle with an inferior glide/slide. During scapular depression the convex clavicle rolls inferiorly and glides/slides superiorly (convex-concave).

    During scapular protraction, (transverse plane movement) the moving clavicle’s concave surface rolls anteriorly as well as glides/slides anteriorly, and during retraction the moving clavicle’s concave surface rolls posteriorly as well as glides/slides posteriorly (concave-convex).

    • Anterior with protraction: 20º - 30º
    • Posterior with retraction: 20º - 30º
    • Superiorly with elevation: 45º
    • Inferiorly with depression: 5º
    • Upward rotation: 45º - 60º
    • Downward rotation: 0º

    Acromioclavicular Joint (AC) (arthrodial - triaxial)

    • Closed-Packed Position: Shoulder abducted 90º
    • Open-Packed Position: Arm resting by side in the fundamental position

    1. Superior & Inferior Acromioclavicular ligaments: reinforce the joint capsule superiorly and inferiorly, limiting superior and inferior displacement of the clavicle respectively.

    1. Coracoclavicular ligament: Divided into the Trapezoid & Conoid portions which attach the coracoid process of the scapula to the lateral inferior surface of the clavicle (with the trapezoid ligament attaching to the trapezoid line anteriorly and the conoid ligament attaching posteriorly to the conoid tubercle). These ligaments add stability to the AC joint and primarily prevent against superior and posterior displacement of the clavicle.

    1. Coracoacromial ligament: This ligament does not cross the AC joint, but rather forms a roof over the glenohumeral joint by attaching to the superomedial surface of the coracoid process and the inferior surface of the acromion process. This ligament provides protection for the underlying subacromial bursa and supraspinatus tendon. It also limits superior displacement of the head of the humerus. However, it has been implicated as a factor in shoulder impingement syndrome.

          

    Figure 2

    Range of Motion: 20-30 degrees total gliding and rotational movement accompanying other shoulder girdle and shoulder joint movements.

    Note: The AC joint allows for independent motion between the scapula and clavicle. If not, the scapula would have to follow the motion of the clavicle degree for degree. Therefore, fine tune adjustments of the scapula at the AC joint are necessary to maintain the proper position of the scapula relative to the rib cage.

    Scapulothoracic Articulation

    The scapulothoratic articulation refers to the movement that occurs between the scapula moving on the ribcage. Movement of the scapula cannot occur without movement of the sternoclavicular and acromioclavicular joints. Again, this is not a true joint but often used to simplify movement analysis of the shoulder girdle.

    Range of Motion:

    Abduction-Adduction: 25°

    Upward-Downward Rotation: 60°

    Elevation-Depression: 55°

     

    Figure 3

    Movements of the Shoulder Girdle (Scapulothoracic Articulation)

    Protraction (abduction) – lateral movement of scapula away from the spine.

    Retraction (adduction) – medial movement of scapula toward the spine.

    Elevation – upward movement of the scapula.

    Depression – downward movement of the scapula.

    Upward rotation – acromion process moves superomedial & inferior angle moves superolateral away from the spine.

    Downward rotation – returning acromion process to its normal position with inferior angle moving inferomedial toward the spine.

    Note: The acromion process of the scapula serves as the reference point when describing scapular movement.

             

    Figure 5

    Consequential Movements of Extreme End of Range Scapular Motion

    Lateral tilt – consequential movement during extreme scapular abduction in which the scapula rotates around its vertical axis, resulting in posterior movement of medial scapular border & anterior movement of the lateral scapular border.

    Medial tilt – return from lateral tilt, consequential movement during extreme scapular adduction in which the scapula rotates around its vertical axis, resulting in anterior movement of medial scapular border & posterior movement of the lateral scapular border.

    Anterior tilt – consequential movement during shoulder joint hyperextension in which the scapula rotates around its frontal axis, resulting in anteroinferior movement of the superior scapular border & posterosuperior movement of the inferior angle.

    Posterior tilt - consequential movement during extreme shoulder joint flexion in which the scapula rotates around its frontal axis, resulting in posteroinferior movement of the superior scapular border & anterosuperior movement of the inferior angle.

    Important Principle: Because of “tonus” a muscle will always exert a pulling force on the bone (or joint) it attaches to or acts upon. As such, if a muscle loses nerve innervation or partial nerve innervation or becomes weak from disuse, then its antagonistic muscle or muscle group will tend to pull the involved segment toward itself, resulting in a notable deformity or altered pattern of movement.

    An “acquired” musculoskeletal deviation or deformity may be the result of injury, disease, or simply the loss of balance in tone that should exist between agonist-antagonistic muscles. This is often the result of a deviation from good and proper posture. See below the changes that occur in the different stages of development of acquired musculoskeletal deformities.

    Stages of Development of Acquired Musculoskeletal Deformities

    First Degree (curable by exercise) – strengthening the weak and stretching the tight

    1. Soft tissue: changes in muscle tone and posture
    2. Bone tissue: no change
    3. Corrective treatment: therapeutic exercise – the patient can perform the exercises to correct the condition

    Second Degree (improvable by exercise)

    1. Soft tissue: contracture
    2. Bone tissue: slight degree of bony change
    3. Corrective treatment: therapeutic exercise performed by another person applying an external force can somewhat correct the condition

    Third Degree (little if any change achieved with exercise)

    1. Soft tissue: contracture
    2. Bone tissue: significant bony change
    3. Corrective treatment: therapeutic exercise can increased function and decrease associated pain but will not resolve postural deviation/deformity

      

    Figure 6

    Guidelines for Muscle Testing and Therapeutic Exercise (Stretching & Strengthening)

    When evaluating a muscle for its strength and range of motion, and to prescribe an exercise program for improvement, the application of some basic principles help the evaluator to effectively apply forces to control movement of the person/limb being evaluated and to better isolate a desired muscle for a better analysis of its functionality. This becomes essential when seeking to appropriately apply forces to strengthen (or stretch) the target musculature.

    1. Isolate the muscle by:
    1. Apply a 90-degree angle of resistance against the distal segment.

    Question: How would you apply this principle to the hamstring muscle group, triceps brachii muscle, and

    pectoralis major muscle?

    Hamstrings?

    Triceps Brachii?

    Pectoralis Major?

    1. Apply that resistance to the distal end of the distal segment
    2. To overcome a musculoskeletal imbalance or deformity:

    Note: On the following pages, skeleton illustrations are provided so students may draw on the associated muscles to help them in their learning of the muscle’s origin, insertion and muscle line of pull.

    Muscles of the Shoulder Girdle - Anterior

    Pectoralis Minor

    Origin:

    Insertion:

    Actions:

    Nerve innervation:

     

    Figure 7

     Figure 8          

    Serratus Anterior

    Origin:

    Insertion:

    Actions:

    Nerve innervation:

    Subclavius

    Origin:

    Insertion:

    Actions:

    Nerve innervation:

    Muscles of the Shoulder Girdle - Posterior

    Levator Scapulae

    Origin:

    Insertion:

    Actions:

    Nerve innervation:

    Rhomboids

    Origin:

    Insertion:

    Actions:

    Nerve innervation:

    Trapezius (upper)

    Origin:

    Insertion:

    Actions:

    Nerve innervation:

    Trapezius (middle)

    Origin:

    Insertion:

    Actions:

    Nerve innervation:

    Trapezius (lower)

    Origin:

    Insertion:

    Actions:

    Nerve innervation:

    Suboccipitals (Not shoulder girdle muscles)

    Origin:

    Insertion:

    Actions:

    Nerve Innervation:

    Force Couples: When 2 or more muscles pull in different directions to accomplish the same motion there is a summative effect, if not greater, in the force production contributing to the similar movement. Consider the combined pull of these three muscles in producing scapular upward rotation. Describe the pull direction for each muscle using a single word.

    • Upper Trapezius pulls: _________________________
    • Lower Trapezius pulls: _________________________
    • Serratus Anterior pulls: _________________________

                   

                   

    Figure 12

    Kyphosis & Upper Crossed Syndrome

    Kyphosis is defined as an excessive posterior curvature (rounding) of the thoracic spine associated with thoracic extensor muscle weakness, usually accompanied with a forward head and rounded shoulders. Upper Crossed Syndrome describes a specific muscle imbalance pattern, with some components similar to kyphosis, and is defined as tightness of the upper trapezius, levator scapulae, and pectoralis major, and weakness of the rhomboids, serratus anterior, middle and lower trapezius, and the deep neck flexors, especially the scalene muscles.

    Forward Head & Rounded Shoulders

    Upper Crossed Syndrome

         Figure 13      

     Figure 14 

    Therapeutic Interventions for Upper Crossed Syndrome

    In the spaces below identify the muscles that are “weak” and those that are “tight” with respect to Kyphosis and Upper Crossed Syndrome and then identify therapeutic interventions to help correct the problem.

    Weak Muscles to be “Strengthened”

    Tight Muscles to be “Stretched”

    Shoulder (Glenohumeral) Joint (enarthrodial - triaxial)

    Closed-Packed Position: Shoulder abducted 90º, and external rotated 90º

    Open-Packed Position: Shoulder abducted 55º, and horizontally adducted 30 º

    1. Glenoid Labrum: serves to deepen the glenohumeral joint and provide attachment for the joint capsule and long head of biceps.
    2. Joint capsule: is lax and permits a significant range of motion, but becomes tauter in the closed pack position.
    3. Superior, Middle, & Inferior Glenohumeral ligaments: are thickenings of the anterior and inferior joint capsule. They prevent anterior and inferior displacement of the humeral head.
    4. Coracohumeral ligament: runs from the coracoid process of the scapula to the greater tubercle of the humerus. It is believed that this ligament’s primary function is to resist gravity’s downward pull on the joint in a resting position. It also limits shoulder external rotation when the arm is to the side, as well as the extremes of shoulder flexion and extension.
    5. Transverse Humeral ligament: binds down the long head of the biceps brachii by attaching from the greater tubercle to the lesser tubercle crossing over the intertubercular/bicipital bicipital groove. Although name as a ligament, it functions as a retinaculum.
    6. Coracoacromial ligament: attaches from the coracoid process of the scapula to the acromion process of the scapula. Provides a protective arch over the glenohumeral joint protecting the soft tissues in the subacromial space (supraspinatus, biceps long head tendon, subacromial bursa, and superior capsule) from superior blows directed downward and protects the glenohumeral joint from superior dislocations of the humerus.
    7. Subacromial bursa: located between the acromion process of the scapula and the rotator cuff tendon, serves to reduce friction between the rotator cuff tendons inferiorly and the acromion process and the deltoid muscle superiorly.

    Shoulder Joint Movements & Average Range of Motion Values

    Flexion – movement of humerus anteriorly from any point in the sagittal plane. (120° or 180° w/ shoulder girdle) 

    Extension – movement of the humerus posteriorly from any point in sagittal plane. (60°)

    Abduction – upward lateral movement of humerus in the frontal plane away from body. (120° or 180° w/ shoulder girdle) 

    Adduction – downward medial movement of humerus in frontal plane toward body from an abducted position. (75°, 0º trunk rest)

    Internal Rotation – movement of the humerus medially in the transverse plane around its long axis toward body midline. (70º)

    External Rotation – movement of the humerus laterally in the transverse plane around its long axis away from body midline. (90º)

    Horizontal Adduction – movement of humerus in a horizontal or transverse plane anteriorly and across the chest. (135º)

    Horizontal Abduction – movement of the humerus in a horizontal or transverse plane posteriorly away from the chest. (45º)

    Note: Reference start position for the “horizontal” movements is shoulder abducted 90°.

     

    Figure 17

    Figure 18 

    Shoulder Joint Arthrokinematics (Roll and Glide/Slide)

    As the shoulder joint performs:

    Scapulohumeral Rhythm

    The shoulder girdle and shoulder joint work together in performing upper extremity movements. However, movement of the shoulder girdle is not dependent on shoulder joint movement by shoulder muscles. During the linear movements of scapular elevation/depression and protraction/retraction, it is possible to move the shoulder girdle up, down, laterally, or medially without moving the humerus. However, shoulder joint movements must accompany the angular movements of scapular upward and downward rotation. The following chart identifies the scapular movements that must occur during various shoulder joint movements.

    Shoulder Joint Movement

    Coupled Shoulder Girdle (Scapular) Movements

    Flexion

    Upward rotation; elevation; protraction

    Extension

    Downward rotation; depression; retraction

    Abduction

    Upward rotation; elevation

    Adduction

    Downward rotation; depression

    Internal Rotation

    Protraction

    Lateral Rotation

    Retraction

    Horizontal Adduction

    Protraction

    Horizontal Abduction

    Retraction

    It is important to note though that the muscles of the shoulder girdle are essential in providing a stabilized or fixated scapula so the muscles of the shoulder joint will have a stable base (bone) from which to exert a pulling force to cause shoulder movement. As such, the shoulder girdle muscles contract to maintain the scapula in a relatively static position (static stabilization) during many shoulder joint movements. As the shoulder joint moves through more extreme ranges of motion, the shoulder girdle muscles contract to move the shoulder girdle (dynamic stabilization) into a more functional position so that further shoulder joint movement can occur, while still providing a stabilizing effect on the scapula.  The result is that most shoulder joint motion requires coordinated joint action of the scapula and clavicle.

    This coupled action between the shoulder girdle and shoulder joint (collectively the shoulder joint complex) is referred to as scapulohumeral rhythm. Without this coupled action the shoulder joint would be limited to only 120° abduction, and high reaching movements would be very restricted. As such, when a person fully abducts the arm 180°, in reality only 120° of motion occurred at the shoulder joint, and 60° was due to scapular motion (upward rotation) at the scapulothoracic articulation with the arm “going along for the ride.”

    For every 2 degrees of shoulder flexion or abduction that occurs, the scapula must upwardly rotate 1 degree. This total scapulohumeral rhythm movement pattern - 120° abduction at the glenohumeral joint and 60° scapular upward rotation at the scapulothoracic articulation - can be divided into an early phase and a late phase. Each phase consisting of 90 degrees total ROM.

                         

    Figure 19

    Early Phase (initial 90 degrees)

    Shoulder abducts 60°, scapula upward rotates 30°.

    This scapular upward rotation of 30° relative to the ribcage is created by two motions:

    1. The clavicle elevates 25° at the sternoclavicular (SC) joint pulling the scapula along for the ride, thereby changing its position and upwardly rotating relative to the ribcage.
    2. The scapula upwardly rotates 5° at the acromioclavicular (AC) joint relative to the clavicle; again, changing its position and upwardly rotating relative to the ribcage.

    Late Phase (final 90 degrees)

    Shoulder abducts another 60°; scapula upwardly rotates another 30°. This additional scapular upward rotation of 30° relative to the ribcage is created by two motions:

    1. The clavicle elevates an additional 5° at the sternoclavicular (SC) joint pulling the scapula along for the ride, thereby changing its position and upwardly rotating relative to the ribcage.
    2. The scapula upwardly rotates an additional 25° at the acromioclavicular (AC) joint relative to the clavicle; again, changing its position and upwardly rotating relative to the ribcage.

    Brachial Plexus: Innervation of the Upper Extremity

    Spinal Nerve Functions – Sensory & Motor Testing of the Upper Extremity

    As previously mentioned, spinal nerves contain both motor fibers and sensory fibers. The motor fibers innervate certain muscles, while the sensory fibers innervate certain areas of skin. A skin area innervated by the sensory fibers of a single nerve root level is known as a dermatome. A muscle or group of muscles predominately innervated by the motor fibers of a single nerve root level is known as a myotome.

    Dermatome: a striplike or area of skin innervated by a single spinal nerve level 

    Myotome: a muscle or group of muscles innervated predominantly by a specific motor spinal nerve level

    Nerves are typically injured through compression or tensile/stretching forces. When a nerve root in the brachial or lumbosacral plexus is damaged, certain patterns of motor and sensory deficits occur in the corresponding limbs. Dermatomes and myotomes are used to evaluate these deficits when nerve root injury is suspected.

    To test for nerve root damage, the corresponding dermatome supplied by that nerve root may be tested for abnormal sensation (Hypoesthesia = decreased sensation, Hyperesthesia = excessive sensation, Anesthesia = loss of sensation, and Paresthesia = numbness, tingling, burning sensation). To test for sensitivity of a dermatome, a pin, cotton ball, paper clip, the pads of the fingers, or fingernails may be used. The patient, with their eyes closed, should be asked to provide feedback regarding their response to the various stimuli. All tests should be compared bilaterally. A cutaneous distribution pattern is an area or patch of skin innervated by a specific sensory peripheral nerve. This nerve maybe be made up of sensory fibers from one or more nerve root levels.

    Figure 21

    C1-Top of head

    C2-Temporal & occipital

    C3-Neck, post cheek

    C4-Superior shoulder & clavicle area

    C5-Anterolateral shoulder and upper arm area

    C6-Lateral forearm, thumb & index finger

    C7-Posterolateral forearm, middle finger

    C8-Medial forearm, ulna border, ring & little finger

    T1-Medial forearm & upper arm

    Figure 22

    Nerve Root

    Dermatome Afferent

    (Sensory)

    Myotome Efferent

    (Motor)

    Functional Application

    C1

    Touch: Vertex of skull

    Upper neck muscles

    Capital flexion and extension

    C2

    Touch: Temple, forehead, occiput

    Upper neck muscles

    -Sensation behind ear and post. skull

    -Capital and upper cervical flexion

    C3

    Touch: Entire neck, posterior cheek, temporal area, under mandible

    Trapezius

    Splenius Capitis

    -Scapula retraction, neck lateral flexion and extension

    -Sensation to cheek and side of neck

    C4

    Touch: Shoulder area, clavicular area, upper scapular area

    Trapezius

    Levator Scapulae

    -Scapula elevation and retraction

    -Sensation to clavicle and upper scapula

    C5

    Touch: Deltoid area, anterior aspect of entire arm to base of thumb

    Supraspinatus

    Infraspinatus

    Deltoid

    Biceps Brachii

    -Shoulder abduction

    -Sensation to lateral side of the arm and elbow

    C6

    Touch: Anterior arm, radical side of hand to thumb and index finger

    Biceps Brachii

    Supinator

    Wrist extensors

    -Elbow flexion, wrist extension

    -Sensation to lateral side of forearm including thumb and index fingers

    C7

    Touch: Lateral arm and forearm to index, long, and ring fingers

    Triceps Brachii

    Wrist flexors

    -Elbow extension, wrist flexion

    -Sensation to middle of anterior forearm and long finger

    C8

    Touch: Medial side of forearm to ring and little fingers

    Ulnar Deviators

    Thumb Extensors

    Thumb Abductors

    -Thumb extension, wrist ulnar deviation

    -Sensation to posterior elbow and medial forearm to little fingers

    T1

    Touch: Medial arm and forearm to wrist

    Intrinsic muscles of hand except for Opp. Pollicis & Abd. Pollicis Brevis

    -Abduction and adduction of fingers

    -Sensation to medial arm and elbow

    T2

    Touch: Medial side of upper arm to medial elbow, pectoral and midscapular areas

    Intercostal Muscles

    -Sensation to medial upper arm, upper chest, and midscapular area

    T3-T12

    Touch: T3-T6, upper thorax

    T5-T7, coastal margin

    T8-T12, abdomen and lumbar region

    Intercostal Muscles

    Abdominal Muscles

    Sensation to chest, abdomen, and low back

    Myotome Testing

    The myotomes may be tested, in the form of isometric resisted muscle testing, for weakness of a particular group of muscles. Results may indicate lesion to the nerve root level, or intervertebral disc herniation pressing on the spinal nerve roots. All tests should be compared bilaterally.

    **Link to view myotome testing procedures: (www.youtube.com/watch?v=rKiTwagLYck‎)

    Upper Extremity Myotomes

    Nerve Root Level

    Patient Position

    Joint & Movement Resisted (tested)

    C1-C2

    Sitting

    Neck flexion

    C3

    Sitting

    Lateral neck flexion

    C4

    Sitting

    Scapular elevation (shrugs)

    C5

    Sitting

    Shoulder abduction

    C6

    Sitting

    Elbow flexion & Wrist extension

    C7

    Sitting

    Elbow extension & Wrist flexion

    C8

    Sitting

    Thumb extension

    T1

    Sitting

    Finger abduction

    Deep Tendon Reflex (DTR):     C5-C6: Biceps Brachii            C7-C8: Triceps Brachii

    Muscles of the Shoulder

    Pectoralis Major (Clavicular)

    Origin:

    Insertion:

    Actions:

    Nerve innervation:

    Pectoralis Major (sternal)

    Origin:

    Insertion:

    Actions:

    Nerve innervation:

    Coracobrachialis

    Origin:

    Insertion:

    Actions:

    Nerve innervation:

    Deltoid (anterior)

    Origin:

    Insertion:

    Actions:

    Nerve innervation:

    Deltoid (middle)

    Origin:

    Insertion:

    Actions:

    Nerve innervation:

    Deltoid (posterior)

    Origin:

    Insertion:

    Actions:

    Nerve innervation:

    Latissimus Dorsi

    Origin:

    Insertion:

    Actions:

    Nerve innervation:

    Teres Major

    Origin:

    Insertion:

    Actions:

    Nerve innervation:

    Supraspinatus

    Origin:

    Insertion:

    Actions:

    Nerve innervation:

    Infraspinatus

    Origin:

    Insertion:

    Actions:

    Nerve innervation:

    Teres Minor

    Origin:

    Insertion:

    Actions:

    Nerve innervation:

    Subscapularis

    Origin:

    Insertion:

    Actions:

    Nerve innervation:

    Rotator Cuff

    The Rotator Cuff is the tendinous cuff formed by the blending together of the insertions of the supraspinatus, infraspinatus, teres minor, subscapularis muscles. Often remembered or referred to as the “SITS” muscles.

    These four muscles have important roles at the shoulder joint. They function to:

    • Initiate and keep the head of the humerus rotating against the glenoid fossa during joint motion

    • Stabilize the head of humerus in the glenoid fossa

    • Decelerate (eccentric) the humerus following forceful concentric motions

    Injuries: Etiology - Repetitive movement of upper limb above horizontal resulting in recurrent inflammation of the rotator cuff tendon(s) (Impingement of supraspinatus on the coracoacromial arch).

     

    Figure 29

    Figure 30

     

    Figure 31

    A Few Shoulder Girdle Review Questions

    1. What are the arthrokinematics that would occur at the sternoclavicular joint when reaching straight up toward the sky?
    2. Why is the trapezius separated into three muscles?
    3. Why are the rhomboids described as one muscle?
    4. What scapular must accompany reaching across a table?
    5. What scapular movement(s) must accompany shoulder abduction?
    6. What scapular movement(s) would accompany closing a window by pulling downward?
    7. What scapular movement(s) would accompany combing your hair in the back?
    8. What is the involved muscle group and involved individual muscles “involved” in maintaining the up position of a dip?
    9. What exercise would you prescribe to strengthen a person’s weak right rhomboids?
    10. What position would you place a patient in (whole body and specific joint) to isolate and stretch their soleus?

    A Few Shoulder Joint Review Questions

    1. What are the shoulder joint movements, scapular movements, and arthrokinematic motions that are required to put your wallet in your right rear pocket with your right hand?
    2. If you were to fall on outstretched arms/hands, what joint and what ligaments supporting that joint might be most

       likely damaged?

    1. What shoulder joint and shoulder girdle movements would be most important to hold a book under your arm?
    2.    What muscles would be working to perform shoulder horizontal abduction from a prone position?
    3.    What shoulder girdle and shoulder joint movements are involved in erasing a whiteboard moving your right hand from left to right?
    4.    While lying on your right side with your left elbow flexed 90° arm held next to body and holding a weight in

       your hand - What is the involved muscle group? What is the prime mover for this?

    1. Which shoulder movements would be contraindicated for a person who recently dislocated their shoulder anteriorly?

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