SHOULDER JOINT (OBSERVATION) PART III

 

• The patient must be suitably undressed so that the examiner can observe the bony and soft tissue contours of both shoulders and determine whether they are normal or symmetric.
• when observing the shoulder , the examiner look at the head , the cervical spine , the thorax ( especially the posterior aspect) and the entire upper limb .
• It is important to observe the patient as he or she removes clothes from the upper body and later replaces them. The patients actions give some indication of functional restriction ,pain or weakness in the upper limb.
• As part of the observation , noting whether the patient can assume a "neutral pelvis" position is important, because an abnormal pelvic position can lead to an abnormal scapulothoracic , glenohumeral and cervical spine position and abnormal kinematics in these joints.

ANTERIOR VIEW 

• The examiner should begin by ensuring that the head and neck are in the midline of the body and observing their relation to the shoulders.
• A FORWARD HEAD POSTURE is often associated with the rounded shoulders , a medially rotated humerus and a protracted scapula resulting in the humeral head translated anteriorly, a tight posterior capsule , tightness of the pectoral , upper trapezius and levator scapulae muscles and weakness of the lower scapular stabilizers and deep neck flexors.

• The examiner should look for the possibility of a STEP DEFORMITY , such a deformity may be caused by the dislocation of acromioclavicular joint . Seen at rest , a step deformity may indicate that the acromioclavicular and coracoclavicular ligaments have been torn. 
  
  
  
• The step deformity may be accentuated by asking the patient to horizontally adduct the arm  or to medially rotate the shoulder and bring the hand up the back as high as possible.

• Occasionally, swelling is evident anterior to the acromioclavicular joint . This is called the fountain sign and indicates the degeneration has caused communication between the acromioclavicular joint and swollen subacromial bursa underneath.
• If a sulcus deformity appears when traction is applied to the arm, it may be caused by multidirectional instability or loss of muscle control due to nerve injury or a stroke, leading to inferior subluxation of the glenohumeral joint . This deformity is lateral to the acromion and should not be confused with a step deformity. This is also referred to as a sulcus sign because of the appearance of a sulcus or groove below the acromion process . 

• Flattening of the normally round deltoid muscle area may indicate an anterior dislocation of the glenohumeral joint or paralysis of the deltoid muscle.

• The examiner should note any abnormal bumps or malalignment in the bones that may indicate past injury such as healed fracture of clavicle.
• In most people, the dominant side is lower than the nondominant side. This difference may be caused by the extra use of the dominant side, which stretches the ligaments, joint capsules, and muscles, allowing the arm to sag slightly. 
• Tennis players and others who stretch their upper limbs in a reaching action show even greater differences, along with gross hypertrophy of the muscles on the dominant side .

• The examiner notes whether the patient is able to assume the normal functional position for the shoulder, which is in the scapular plane with 60° of abduction and the arm in neutral or no rotation. 

• In this position, or with the arm abducted to 90°, rupture or congenital absence of the pectoralis major may be evident.
• Rupture of the pectoralis major is often accompanied by a tearing sensation and pop along with weakness, painful limitation of movement, and ecchymosis .

• If the patient’s arm is medially rotated from this position to bring the hand into midline, the biceps tendon is forced against the lesser tuberosity of the medial wall of the bicipital (intertubercular) groove. If this position is maintained for long periods, there may be increased wear of the biceps tendon, which can lead to bicipital tendinitis or paratenonitis
• If the arm is horizontally adducted while it is medially rotated, anterior pain indicates impingement symptoms .
• The width and depth of the bicipital groove may vary possibly leading to problems if the shoulder is overused. 
• Especially wide or deep grooves lead to the greatest problems. 
• The wide grooves tend to allow the tendon too much lateral movement, leading to inflammation of the paratenon (paratenonitis)
• The deep grooves tend to be too narrow, compressing the tendon, especially if it becomes inflammed .

POSTERIOR VIEW 

• When viewing the patient from behind , the examiner again notes bony and soft-tissue contours and body alignment especially scapular malpositioning.
• The scapula plays a major role in the shoulder.
•  First, it provides an origin for the rotator cuff muscles as well as the biceps and triceps muscles and, therefore, provides a stable dynamic base from which these muscles act. 
• Second, it maintains the glenohumeral alignment within physiological limits that facilitates congruency and concavity compression capability at the glenohumeral joint through the full ROM. 
• Third, the attachment of the acromion to the clavicle leads to scapular upward rotation and posterior tilt to allow maximum arm elevation. 
• Finally, the scapula facilitates force transfer from the shoulder to the core (and vice versa) acting like a funnel for efficient energy transfer. This transfer of forces can involve the whole kinetic chain, and by using this “chain” correctly, the patient can decrease the stresses to the shoulder itself.

• Atrophy of the upper trapezius may indicate spinal accessory nerve palsy.
• Atrophy of supraspinatus or infraspinatus may indicate supraspinous nerve palsy. 

The spines of the scapulae, which begin medially at the level of the third thoracic (T3) vertebra, should be at the same angle. The scapula itself should extend from the T2 or T3 spinous process to the T7 or T9 spinous process of the thoracic vertebrae.

Sobush and associates developed a method for measuring the scapular position called the Lennie test.

In this test, they measured from the spinous processes horizontally to three scapular positions: the medial aspect of the most superior point (superior angle), the root of the spine of the scapula, and the inferior angle

• If the scapula is sitting lower than normal against the chest wall, the superior medial border of the scapula may “washboard” over the ribs, causing a snapping or clunking sound (snapping scapula) during abduction and adduction.Other causes of snapping may be spinal kyphosis, rounded shoulders, forward tipped scapula, and a chin poking posture
• SCAPULAR DYSKINESIA or SCAPULAR DYSFUNCTION, although not an injury itself, can lead to altered glenohumeral joint angulation, abnormal stress on shoulder ligaments, altered subacromial space, overload of the acromioclavicular joint, increased strain on the scapular stabilizing muscles, altered muscle activation, and modified arm position and motion.These alterations are commonly the result of an excessively protracted scapula during arm motion. 
• scapular dysfunction or dyskinesia into four movement patterns. 

1. Type I shows the inferior medial border being prominent at rest and the inferior angle tilts dorsally with movement (scapular tilt), while the acromion tilts anteriorly over the top of the thorax.

•  It may be seen at rest or during concentric or eccentric movement. 
• If the inferior border tilts away from the chest wall, it may indicate the presence of weak muscles (e.g., lower trapezius, latissimus dorsi, serratus anterior) or a tight pectoralis minor or major pulling, or tilting, the scapula forward from above.

2.Type II is the classic winging of the scapula with the whole medial border of the scapula being prominent and lifting away from the posterior chest wall both statically and dynamically . 

• It too may be seen at rest or during eccentric or concentric movements. 
• This deformity may indicate the presence of a superior labrum anterior to posterior (SLAP) to the biceps lesion; weakness of the serratus anterior; rhomboids; lower, middle, and upper trapezius; a long thoracic nerve problem; or tight humeral rotators

3. Type III is illustrated by the superior border of the scapula being elevated at rest and during movement; a shoulder shrug initiates the movement, and there is minimal winging. 

• This deformity is seen with active movement and may result from overactivity of the levator scapula and upper trapezius along with imbalance of the upper and lower trapezius force couple . 
• It is associated with impingement and rotator cuff lesions.

4.In the type IV pattern, both scapulae are symmetrical at rest and during motion; they rotate symmetrically upward with the inferior angles rotating laterally away from midline (rotary winging). 

• It is seen during movement and may indicate that the scapular control muscles are not stabilizing the scapula.

DYNAMIC SCAPULAR MOTION TEST 

• Test for scapular dyskinesia 
• The patient while holding a 3lbto 5lb(1.4kg to 2.3kg) weight in the hand , is asked to fully elevate and lower the arms three to five times in to forward flexion and scaption .
• The examiner watches for prominence of the medial border of the scapula(classic winging) which indicates a positive test.

• PRIMARY SCAPULAR WINGING implies the winging is the result of one of the scapular muscles stabilizers that , in turn , disrupts the normal muscle force couple balance of the scapulothoracic complex.
• SECONDARY SCAPULAR WINGING implies that that normal movement of the scapula is altered because of the pathology in the glenohumeral joint .
• DYNAMIC SCAPULAR WINGING (winging with movement) may be caused by a lesion of the long thoracic nerve affecting serratus anterior , trapezius palsy ( spinal accessory nerve), rhomboids weakness,multidirectional instability,voluntary action or a painful shoulder resulting in splinting of the glenohumeral joint which in turn causes reverse the scapulohumeral rhythum .Commonly, with pathology the scapular control muscles are weak and cannot counteract this action , resulting in protraction of scapula and dynamic winging.

        The two other common causes of dynamic winging are long thoracic nerve palsy and spinal accessory nerve palsy, cause different scapula positioning and different winging patterns.

• SPINAL ACCESSORY NERVE PALSY causes the scapula to depress and move laterally with inferior angle rotated laterally.
• If the TRAPEZIUS is weak or paralyzed , the winging of scapula occur before 90 degree abduction and there is little winging on forward flexion .
• LONG THORACIC NERVE PALSY causes the scapula to elevate and move medially with inferior angle rotated medially.
• If the SERRATUS ANTERIOR is weak ,  the winging of scapula on abduction and forward flexion
• RADICULOPATHIES at c3,c4(trapezius) ,c5(rhomboids)and c7(serratus anterior and rhomboids) can also cause winging.
• STATIC WINGING is usually caused by a structural deformity of the scapula,spine,clavicle or ribs.
• SPRENGEL'S DEFORMITY which is a developmental condition leading to a high or undescended scapula , is rare , but it is the most common congenital deformity of the shoulder complex.

With this deformity , the scapular muscles are poorly developed or are replaced by the fibrous band.

The condition may be unilateral or bilateral 

The range of the shoulder abduction decreases leading to the decreased shoulder function .

usually the scapula is lower than the normal and is medially rotated.

It may be associated with other anomalies.