Shoulder injuries in athletics, especially throwing sports, is a relatively common phenomenon. Assessment and evaluation of shoulder problems requires a systematic approach that should be both comprehensive and efficient. This paper seeks to outline a sequential process that incorporates a number of different components of a thorough examination: taking a history, inspecting the shoulder, palpation, assessing active and passive range of motion, strength testing, and performing special tests.

COMMON SHOULDER INJURIES AMONG ATHLETES -- EVALUATION & MANAGEMENT

The evaluation of shoulder injuries in athletes is a complex process that relies on accurate diagnosis before proper management can be effective. It is one of the most difficult areas of the body to assess given its intricate makeup and structure and the demands placed on it in overhand athletics. What seeks to confuse issues further is that pain complaints in the shoulder could very well be indicative of some other pathology. Referred pain from a nerve root injury, neurovascular compromise, intrathoracic problems of the internal organs, and even spinal conditions can make it even more difficult to accurately assess an athlete. A careful history and thorough physical examination are critical before a plan of action can be outlined.

Shoulder injuries can be broken down into two basic types of injuries: acute and chronic. It is essential that the examiner determine whether the injury was of sudden onset or a slow progression of symptoms. The history is one of the first and most important steps in the evaluation of any shoulder injury. If the injury was of sudden onset, then a detailed history pertaining to the exact mechanism should be obtained from the athlete to determine if outside resistive forces, direct trauma, or other precipitating factors could have caused the injury (1). If the injury has been painful for several days or weeks, then a thorough history should be reviewed for any causative or predisposing factors. Physical examination will confirm or refute the diagnosis suggested by the history (2).

This article discusses necessary steps in the evaluation process: taking a history, inspecting the shoulder, palpating, assessing both active and passive range of motion, strength testing, conducting special tests, and other considerations. Emphasis will be placed on assessment procedures that incorporate all these components into each injury category. Surgical options will be discussed as well as some of the rehabilitation exercises and 'pearls' that can be provided to patients.

Anatomy

The shoulder is a complex ball and socket joint made up of 5 articulations: glenohumeral (GH), scapulothoracic (ST), sternoclavicular (SC), acromioclavicular (AC), and coracoclavicular (CC). The arm is able to move and perform as it does through a synchronous coordinated movement of all of these joints. Though this article does not cover the specific biomechanics of these movements, a basic understanding of the general mechanics of these joints greatly enhances the ability to conduct a thorough examination.

The shoulder complex is comprised of three bones: the scapula, humerus, and clavicle. They, through the use of the 5 articulations, are able to provide an extraordinary range of movements--but all at an increased risk for injury. The glenohumeral joint is stabilized somewhat by the glenoid labrum, a fibro-cartilaginous ring that gives a little more depth to the shallow glenoid fossa. The capsule surrounds this entire structure and is further stabilized by the musculotendinous bundle of rotator cuff muscles. The acromion process comes up over the top and forms the subacromial space through which passes the supraspinatus muscle of the rotator cuff and the subacromial bursa. The narrow subacromial arch is further shortened by the coracoacromial and coracohumeral ligaments and is the primary area of shoulder impingement injuries (3).

Major muscles of the shoulder complex are listed below followed by their primary action (4,5) (IR=internal rotation; ER=external rotation): 

Taking a History

Paying close attention to the specific details surrounding the injury is the first critical step in accurately assessing any athletic injury. Questions should be specific enough that you can get the information you need. For acute injuries, details should be directed towards the mechanics of the injury and what might have been the predisposing factor. Important questions to ask are:

A careful examination of the shoulder joint begins with a visual inspection of the athlete's neck, shoulders, scapulae, and upper thorax with their entire upper body exposed above the breast line. A systematic approach should be taken by starting at the neck and working down both shoulders looking for asymmetry between contralateral bony and soft tissue contours, the attitude of the shoulder and how they are holding it, deformity, atrophy, or any obvious scars or marks (6). Be sure to compare bilaterally and to check anterior, posterior and lateral postural positioning.

When inspecting the shoulder anteriorly, an obvious asymmetry at the AC joint with the involved side being more prominent is indicative of an AC separation. Discoloration and ecchymosis may be apparent from a rotator cuff injury, fracture, significant shoulder contusion ('shoulder pointer'), or biceps rupture. Significant atrophy of the deltoid muscle or loss of the lateral muscle contour could indicate a glenohumeral dislocation or a neurovascular lesion. An indentation of the upper biceps region and/or a bunching up of the biceps tendon distally with elbow flexion signifies a rupture of the biceps tendon. Posteriorly, if the scapulae appear uneven, then it could be a sign of scoliosis or poor muscle balance. Winging of the scapulae usually means that there is weakness of the serratus anterior muscle and often becomes more apparent with muscle testing. However, if it is unilateral, then it could be a sign of an injury to the long thoracic nerve (7). Wasting of the infraspinatus fossa below the scapular spine is a hallmark of rotator cuff pathology. Laterally, if they have an obvious forward head and rounded shoulders posture than they could have an impingement syndrome at the AC joint.

Palpating the Shoulder

Standing from behind, the athlete is palpated bilaterally for areas of tenderness, obvious deformities and temperature changes. Beginning anteriorly and moving laterally (8):

Active movements (AROM) are assessed first when checking range of motion and are usually done in such a way that the painful movements are performed last. The active movements that are to be evaluated with their corresponding normal ranges are (7,9): 

Some other important things to note when assessing AROM are painful arc, which is tested while the patient abducts the arm. If pain is elicited between about 45 and 120 degrees but not at the beginning or end ranges, then a positive painful arc is present. It happens as a result of impinging tissue on the acromial arch and the coracoacromial ligament and is usually indicative of subacromial bursitis, tendinitis of the rotator cuff, or impingement syndrome. If the patient notes a consistent click during certain movement patterns, then it is possible that they have a tear of their glenoid labrum or GH capsule. Scapulohumeral rhythm is monitored for signs of guarding or compensating. This is determined by the examiner observing the movement of the scapula in relation to the humerus and during abduction, there is a 2:1 ratio of humerus to scapula motion. Movement that is much more excessive at the scapula versus the GH joint could be a sign of frozen shoulder or rotator cuff tear.

Passive range of motion (PROM) is assessed with the patient supine and checking all ranges for pain (making sure the patient is as relaxed as able), restrictions (noting the end-feel of the movement), or excessive motion (hypermobility can be a sign of glenohumeral instability).

A couple of general guidelines are if there is limited AROM and PROM, then one should suspect a frozen shoulder, fracture or chronic bursitis. Limited AROM but full PROM is indicative of a RC tear. If there is full AROM and PROM but one resisted movement hurts, it is a sign of tendinitis (10).

Strength Testing

Resisted isometric movement tests are performed with the patient lying supine. By carefully noting which movements cause pain, the examiner can begin to determine which muscles are involved. This is when one's knowledge of anatomy and its relationship to muscle function plays a large role. The movements to be tested isometrically are the same as those tested for AROM with resisted elbow flexion and extension added. Carefully record which motions are painful, guarded and/or weak. A general guideline for patterns of pain and weakness are as follows (10): 

Upon completion of the initial evaluation, the examiner should at this time have a pretty good idea of which structures are involved. At this point, there are special tests that will help to confirm or refute the other findings. It is also important that only the only the relevant special tests be performed as there are too many to perform routinely (6, 9, 10).

Supraspinatus Test/Centinela Supraspinous Test--the patient's arms are brought into 90 degrees of forward flexion and then into 30 degrees of horizontal abduction, the arms are then internally rotated so the thumbs are pointed downward. The evaluator applies downward pressure while the athlete resists and a positive response is if there is pain and/or weakness, indicating supraspinatus involvement.

Drop Arm Test--also a test for rotator cuff tears (especially the supraspinatus), the examiner abducts the arm to about 90 degrees and then has the patient slowly lower the arm to their side. A positive test is if the patient is unable to lower arm or is able to do so with considerable pain and shoulder hiking. Another possible result is if they are unable to actively lower the arm but they are able to hold it at shoulder height, the practitioner can give a light tap on the wrist and the arm will fall.

Speed's Test/Biceps Test--The examiner resists forward flexion with the arm in supination and the elbow completely extended. Pain and/or weakness in the bicipital groove indicates a biceps strain or bicipital tendinitis.

Test for a Subluxing Biceps Tendon and Bicipital Tendinitis--the patient lies supine with the arm in extension off the end of the table and the forearm in pronation, slowly extend the arm. If this elicits pain in the bicipital groove, then this is a sign of tendinitis. Now bring the arm slightly out of extension and then externally rotate the arm with the examiner's thumb on the bicipital groove. A positive test is if the biceps tendon pops out of the groove indicating a tear of the transverse humeral ligament.

Impingement Sign--the arm is forward flexed to 90 degrees passively, the proximal humerus is internally rotated with the elbow bent and a positive sign is if the patient complains of reproducible pain at the subacromial space. An alternative method is to forward flex the arm to its overhead end-range and then forcibly put over pressure to the arm trying to "jam" the greater tuberosity into the acromion.

Cross Adduction Test--the arm is brought to 90 degrees of forward flexion and then passively brought across the front of the body. A positive test is if pain is elicited at the anterior shoulder, indicating a possible subcoracoid bursitis or labral/capsular tear.

Apprehension Test--the patient lies supine and the examiner brings the arm into 90 degrees of abduction, elbow flexion and external rotation. The arm is externally rotated while the examiner watches the reaction of the patient. A positive test result is achieved if the patient has a look of apprehension or alarm on their face and state that they feel that the shoulder will dislocate if it is pushed any further. The examiner is also trying to assess the feel of the mobility of the GH joint for any obvious laxity (looseness) compared with the other side. Care must be taken to perform this test slowly as it can sublux the humeral head in very lax patients.

Relocation Test--immediately following the Apprehension Test and any positive results, if an anterior force is applied on the posterior aspect of the humeral head, this translation increases the pain. If a posterior force is applied in the same testing position and the patient's symptoms are reduced, this suggests that the pain is as a result of the head pressing anterior on the static stabilizers often found in subluxation (11).

Load and Shift Test--the patient is supine and the examiner grasps the proximal humeral head and a gentle load is applied anteriorly, posteriorly, and inferiorly to assess the amount of joint play in the GH joint. A positive test is if the humeral head excessively translates compared to the contralateral side--especially if it feels as if the head subluxes over the rim of the labrum. This is an indicator of a uni- or multi-directional instability. Occasionally, a click might be elicited with testing and could be sign of a torn labrum (11).

In conclusion, a few basic tips that an examiner can provide to their patients for some of the more common diagnoses are:   

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