Shoulder Injuries

3 Shoulder Injuries





Background


Normal function of the “shoulder complex” requires the coordinated movements of the sternoclavicular (SC), acromioclavicular (AC), and glenohumeral (GH) joints; the scapulothoracic articulation; and the motion interface between the rotator cuff and the overlying coracoacromial arch. Successful elevation of the arm requires a minimum of 30 to 40 degrees of clavicular elevation and at least 45 to 60 degrees of scapula rotation. Motion across these articulations is accomplished by the interaction of approximately 30 muscles. Pathologic changes in any portion of the complex may disrupt the normal biomechanics of the shoulder.


The primary goal of the shoulder complex is to position the hand in space for activities of daily living. During overhead athletic activities such as throwing and serving, the shoulder’s secondary function is as the “funnel” through which the forces from the larger, stronger muscles of the legs and trunk are passed to the muscles of the arm, forearm, and hand, which have finer motor skills. The ability to execute these actions successfully comes from the inherent mobility and functional stability of the GH joint.


“Unrestricted” motion occurs at the GH joint as a result of its osseous configuration (Fig. 3-1). A large humeral head articulating with a small glenoid socket allows extremes of motion at the expense of the stability that is seen in other joints (Table 3-1). Similarly, the scapula is very mobile on the thoracic wall. This enables it to follow the humerus, positioning the glenoid appropriately while avoiding humeral impingement on the acromion. Osseous stability of the GH joint is enhanced by the fibrocartilaginous labrum, which functions to enlarge and deepen the socket while increasing the conformity of the articulating surfaces. However, the majority of the stability at the shoulder is determined by the soft tissue structures that cross it. The ligaments and capsule form the static stabilizers and function to limit translation and rotation of the humeral head on the glenoid. The superior GH ligament has been shown to be an important inferior stabilizer. The middle GH ligament imparts stability against anterior translation with the arm in external rotation and abduction less than 90 degrees. The inferior GH ligament is the most important anterior stabilizer with the shoulder in 90 degrees of abduction and external rotation, which represents the most unstable position of the shoulder (Fig. 3-2).



Table 3-1 Normal Joint Motions and Bony Positions Around the Shoulder Joint




































Scapula
Rotation through arc of 65 degrees with shoulder abduction
Translation on thorax up to 15 cm  
Glenohumeral Joint
Abduction 140 degrees
Internal/external rotation 90 degrees/90 degrees
Translation  
Anterior–posterior 5–10 mm
Inferior–superior 4–5 mm
Total rotations  
Baseball 185 degrees
Tennis 165 degrees


The muscles make up the dynamic stabilizers of the GH joint and impart stability in a variety of ways. During muscle contraction, they provide increased capsuloligamentous stiffness, which increases joint stability. They act as dynamic ligaments when their passive elements are put on stretch (Hill 1951). Most important, they make up the components of force couples that control the position of the humerus and scapula, helping to appropriately direct the forces crossing the GH joint (Poppen and Walker 1978) (Table 3-2).


Table 3-2 Forces and Loads on the Shoulder in Normal Athletic Activity












































Rotational Velocities
Baseball 7000 degrees/sec
Tennis serve 1500 degrees/sec
Tennis forehand 245 degrees/sec
Tennis backhand 870 degrees/sec
Angular Velocities
Baseball 1150 degrees/sec
Acceleration Forces
Internal rotation 60 Nm
Horizontal adduction 70 Nm
Anterior shear 400 Nm
Deceleration Forces
Horizontal abduction 80 Nm
Posterior shear 500 Nm
Compression 70 Nm

Proper scapula motion and stability are critical for normal shoulder function. The scapula forms a stable base from which all shoulder motion occurs, and correct positioning is necessary for efficient and powerful GH joint movement. Abnormal scapula alignment and movement, or scapulothoracic dyskinesis, can result in clinical findings consistent with instability and/or impingement syndrome. Strengthening of the scapular stabilizers is an important component of the rehabilitation protocol after all shoulder injuries and is essential for a complete functional recovery of the shoulder complex.


In most patients, rehabilitation after a shoulder injury should initially focus on pain control and regaining the coordinated motion throughout all components of the shoulder complex. Once motion is regained, attention is shifted to strengthening and re-educating the muscles around the shoulder to perform their normal tasks. To reproduce the precision with which the shoulder complex functions, the muscles need to be re-educated through “learned motor patterns.” These patterns position the shoulder complex in “predetermined” ways and activate the muscles in precise synchronization to maximize recovery of function. Associated conditioning of the lower extremities and trunk muscles is extremely important because more than 50% of the kinetic energy during throwing and serving is generated from the legs and trunk muscles. Therefore, rehabilitation of all components of the kinetic chain is required before the successful return of competitive or strenuous overhead athletic activities.



General Principles of Shoulder Rehabilitation


Marisa Pontillo, PT, DPT, SCS


Many pathologic conditions can affect the shoulder complex. As with other parts of the musculoskeletal system, these can be the result of either acute trauma or repetitive microtrauma. Acute or chronic injury may result in the disruption of motion, strength, kinesthesia, or dynamic stability. As rehabilitation professionals, we can positively influence all of these components.


It is important to recognize that the shoulder complex consists of four joints that work in concert, resulting in optimal shoulder motion. All joints should be evaluated and impairments subsequently should be treated. On evaluation, obvious findings are easily diagnosed and may involve mechanical disruptions such as gross instability, massive muscle tears, or severe impairments such as significant loss of motion or strength. These contrast subtle findings that are more difficult to diagnose and just as difficult to treat. Subtle findings may include, but are not limited to, increased humeral translation from a loss of glenohumeral internal rotation, superior humeral head migration as a result of rotator cuff weakness, or abnormal scapular static positioning or altered movement patterns secondary to weakness of the trapezius or serratus anterior muscles. For successful rehabilitation, recognition and treatment of the pathology are as important as understanding its impact on normal shoulder function. Regardless of underlying pathology, the goals of rehabilitation are functional recovery and returning patients to their previous level of activity.


The most important factor that determines the success or failure of a particular shoulder rehabilitation protocol is establishing the correct diagnosis. In the present health care environment, patients may be referred to physical therapy by primary care physicians. If after evaluation and treatment the patient does not progress, careful re-evaluation followed by referral to appropriate imaging (i.e., radiography, computed tomography, or magnetic resonance imaging) should be considered. For example, a locked posterior dislocation of the humeral head is missed 80% of the time by the initial treating physician and may only be apparent through axillary lateral radiographs.


On evaluation, it is important to recognize that certain “abnormalities” are in fact adaptations that are necessary to the patient’s sport. For example, throwing athletes will acquire looseness in the anterior capsule and increased external rotation at 90 degrees of abduction. These may result in other conditions such as glenohumeral internal rotation deficit (GIRD) or secondary impingement. However, maintenance of this excessive external rotation is imperative for optimal throwing mechanics.


Designing a rehabilitation program should take several factors into account:







Rehabilitation should focus on the elimination of pain and the restoration of functional movement through dynamic stability of the rotator cuff and scapular musculature. With all therapeutic activities, painful arcs and positions that may exacerbate impingement or subluxation should be avoided.


Tissue irritability is a major factor in determining prognosis and goals, initial interventions, and the rate of exercise progression. Because this will reflect the patient’s level of inflammation, it should be assessed at initial evaluation and throughout the course of care to guide treatment.


In general, rehabilitation after an injury or surgery should begin with early motion to help restore normal shoulder mechanics. This may involve active or passive range of motion (ROM) or joint mobilizations, respecting the biomechanical properties of healing tissue. The benefits of early mobilization, well established in the literature in other parts of the body, include decreased pain and enhanced tendon healing. Strict immobilization can be responsible for the development of further impairments through rotator cuff inhibition, muscular atrophy, and poor neuromuscular control. A lack of active motion within the shoulder complex compromises the normal kinematic relationship between the glenohumeral and the scapulothoracic joints and can lead to rotator cuff abnormalities. Motion exercises should not be performed if the clinician and referring physician believe that the surgical repair may be compromised. Low-grade joint mobilization may help with pain modulation through activation of type I mechanoreceptors without causing stretching or deformation of the capsule.


Strengthening should respect healing structures while progressing the patient to his or her functional goals. To this end, the appropriate mode of exercise should be considered: isometric, concentric, or eccentric training or open- or closed-chain activities. One must also consider the resultant amount of muscle activation with each activity. These factors will dictate the suitability of the amount of joint loading to the patient’s current phase of rehabilitation.


Involving the scapulothoracic musculature is an important component of shoulder rehabilitation. Scapulothoracic muscles provide a stable base for the shoulder and are imperative for optimal shoulder function through their role as dynamic stabilizers to the scapulothoracic joint. Scapular weakness may contribute to subacromial impingement by affecting muscle firing patterns and scapulohumeral rhythm.


Integration of the kinetic chain has been advocated for thorough rehabilitation of the shoulder. Muscle activation of the upper extremity occurs in a proximal-to-distal sequence and reflects innate motor control patterns. The trunk and legs contribute to upper extremity motion through transferring energy and force to the upper extremity. Functional movement patterns that integrate the kinetic chain should be integrated into the rehabilitation process.


Therapeutic exercise should involve not only strengthening shoulder girdle musculature, but also neuromuscular re-education. The role of the rotator cuff is to provide dynamic stability to the GH joint, working with the scapular stabilizers to move the upper extremity in a consistent, coordinated fashion. Muscle coordination patterns and kinesthesia can be enhanced through specific intervention techniques. Perturbation training, rhythmic stabilization, and/or proprioceptive neuromuscular facilitation activities may be useful components of treatment.


With the shoulder complex, it is important to work from less to more provocative positions. For example, external rotation performed with the arm by the side will potentially be less aggravating than if performed at 90 degrees of abduction. However, it may be important to a patient’s functional goals to perform work or a sport overhead; thus patients may need to progress to therapeutic activities in this position. In addition, although performing prone horizontal abduction with full external rotation demonstrates high electromyographic (EMG) activity of the supraspinatus, it may invoke symptoms for patients with impingement syndrome. In the early phases of rehabilitation, substitutions such as standing scapular plane elevation may be more appropriate.


Return-to-sport activities should be incorporated in the final phases of rehabilitation. Once a patient demonstrates sufficient strength and neuromuscular control to be cleared for plyometric exercises, these exercises will improve power and encourage maximal firing of the rotator cuff and scapular muscles to provide a necessary transition to high-speed activities. Additionally, interval sports programs (discussed later in this chapter) will train the musculature to the specific demands of an individual’s sport.


Returning to weight lifting may be a goal for many. Progressive resistive training is permissible when there is no to minimal pain, full ROM, and adequate strength to accommodate for imposed demands, provided sufficient time has elapsed postinjury to support adequate tissue healing. Education regarding adaptations of equipment and upper extremity positioning and the avoidance of provocative positioning is mandated. For example, patients with posterior instability should avoid “locking out” the upper extremity during a bench press because of the increased posterior shear in this position. Likewise, patients with anterior instability will want to avoid positions that place the anterior capsule on stretch (90 degrees of shoulder abduction and 90 degrees of external rotation).


In addition to clinical re-evaluations, upper extremity or shoulder-specific outcome forms will provide subjective information about a patient’s self-reported pain, satisfaction, and functional status. These have been shown to demonstrate reliability, validity, and responsiveness to change over time. The Penn Shoulder Score, modified American Shoulder and Elbow Surgeons score; Western Ontario Shoulder Instability Index; Simple Shoulder Test; and Disabilities of the Arm, Shoulder, and Hand score are examples of outcome scores commonly used for these purposes. Outcome scores can aid in monitoring progress and provide documented information as to the effectiveness of current treatment.



Importance of the History in the Diagnosis of Shoulder Pathology


Richard Romeyn, MD, and Robert C. Manske, PT, DPT, SCS, MEd, ATC, CSCS


The patient history is the first step in the evaluation of shoulder symptoms. The possible diagnoses will subsequently be confirmed or refuted during the physical examination and radiographic evaluation. Because different pathologies may manifest themselves with similar presenting complaints, with the underlying problem producing only secondary symptoms (although these will be the ones apparent to the patient), assessment of the shoulder is uniquely challenging, and an illuminating history requires the examiner to be well organized and ask specific and focused questions because patients generally do not readily volunteer all necessary information.


When taking a history, the crucial elements about which one must inquire are as follows:








Following are the most commonly encountered primary shoulder pathologies to keep in mind when evaluating a symptomatic shoulder, along with the most likely elements in the history that will suggest them. Also always keep in mind the fact that more than one pathology may be present concurrently.















Structural Injury to the Rotator Cuff


Although traumatic tears of the rotator cuff have been reported even in children, structural injury to the cuff is most characteristic in those older than age 40 years. Rotator cuff tears are so characteristic of the elderly population that anyone older than age 60 with shoulder pain can be presumed to have a rotator cuff tear until proved otherwise. Younger patients with cuff symptoms tend to have only irritation of the rotator cuff (tendinosis) rather than structural injury, with their pathology and symptoms frequently being the secondary manifestation of occult primary pathology such as glenohumeral instability, tears of the superior labrum, scapulothoracic dyskinesia, core stability deficits, or poor biomechanics.


Rotator cuff pathology may be of insidious onset, but it is most often produced by a traumatic event or acute overuse, particularly with an abduction/external rotation mechanism. In the elderly, rotator cuff tears frequently occur during falls. Night pain is characteristic of primary rotator cuff pathology and may be severe enough to prevent sleep or awaken the patient from sleep if she or he rolls onto the affected shoulder. Patients with cuff disease find relief by placing the affected arm overhead with the hand behind the head (the so-called Saha position). Pain is minimal with use of the arm below breast level and is maximal between 90 and 120 degrees of active elevation/abduction. Lowering the arm from the overhead position is often more painful than raising it. Patients may describe crepitus, which is associated with chronic full-thickness cuff tears or thickening of the cuff during chronic tendinosis and scarring of the subacromial space.


Pain is localized to the subacromial area or the anterior/lateral corner of the acromion, with radiation down the lateral arm to the vicinity of the deltoid insertion. The pain is characteristically of a dull aching quality, with the superimposition of a sharper stabbing pain with use of the arm in the overhead position or with internal rotation. Rotator cuff pain does not radiate distal to the elbow.


Rotator cuff pain is characteristically mitigated by anti-inflammatory medications, especially subacromial corticosteroid injections, but with diminishing returns over time.



Glenohumeral Instability


Glenohumeral instability is the most common underlying pathology producing shoulder symptoms in patients younger than 30 years of age. In children and teenagers, it is virtually the only likely pathology. In the elderly population, instability is associated with massive rotator cuff tears. In many instances, the symptoms reflective of glenohumeral instability had a traumatic origin of which the patient is aware. Apprehension with use of the arm in a specific position is a subjective sign of instability, but it is important to keep in mind that a great many patients with glenohumeral instability have no subjective awareness of that fact.


When the diagnosis of instability is suspected, an important goal when taking the history is to ascertain: (1) the degree of instability (subluxation versus dislocation), (2) the onset (traumatic versus atraumatic or overuse), (3) the direction or directions of instability (anterior, posterior, or multidirectional), and (4) whether there is a voluntary component.


The most common direction of instability, whether traumatic or occult, is anterior/inferior. The direction of instability can be determined during the history with specific questions related to the arm position that produces symptoms: external rotation, with or without abduction reflects an anterior/inferior laxity pattern (e.g., pain with the cocking position during throwing). Pain during the follow through when throwing or during activities that position the arm in forward flexion/adduction/internal rotation suggests posterior instability. Pain that is associated with activities that apply primarily inferior distraction force to the shoulder, such as carrying a heavy object like a suitcase or a pail of water, suggests inferior capsular laxity and multidirectional instability.


Subtle glenohumeral instability is associated with a nondescript level of discomfort and diffuse pain about the shoulder girdle. The discomfort is characteristically poorly localized and may be scapular and at the posterior joint line, or anterior subacromial mimicking rotator cuff discomfort. Often patients will relate that use of the arm overhead produces numbness and tingling radiating down the arm without a specific dermatomal distribution. This is known as the “dead arm syndrome.” A history of repetitive microtrauma, such as participation in swimming or throwing sports, without proper pre-participation conditioning is characteristically present when atraumatic glenohumeral instability produces symptoms in teenage athletes. Although labral pathology is often associated with glenohumeral instability, its presence cannot generally be predicted by specific questions during the history.


If occult glenohumeral instability was not recognized, there are associated deficits in scapulothoracic function and core stability, or poor technique was not adequately addressed during treatment, there may be a history of failed medication use, rehabilitation, or surgery.












General shoulder rehabilitation goals



Range of Motion


Once the intake evaluation is completed, the therapist should be more comfortable anticipating the patient’s response to the therapeutic regimen. One of the main keys to recovery is to normalize motion. Early professions relied on visual estimations or “quick” tests to assess shoulder motion. These tests include combined shoulder movements such as the Apley’s scratch test (Fig. 3-3), reaching across the body to the other shoulder (Fig. 3-4), or reaching behind the back to palpate the highest spinous process (Fig. 3-5). These quick tests are great to observe for overall asymmetry, but they cannot give an idea of isolated losses objectively.





Even more important is regaining normal arthrokinematic motions at the shoulder. Active shoulder range of motion is always gathered before passive motions (Manske and Stovak 2006). Active shoulder ROM is seen in Table 3-3 (Manske and Stovak 2006). Many times, gross overall shoulder motion may only appear to be slightly limited, whereas arthrokinematic motion is drastically dysfunctional. For example, it is not uncommon for a patient to have full glenohumeral motion, yet impinge as a result of altered scapulohumeral motion from a restricted inferior or posterior shoulder capsule creating obligate humeral translations.



Therefore, it is imperative to also ensure evaluation of isolated glenohumeral motions is performed. One of the more common problematic limited motions with a variety of shoulder conditions is that of the posterior or inferior shoulder structures. Debate continues as to whether this is a result of capsular or other soft tissues. Regardless, it becomes an issue whenever elevation of the glenohumeral joint is required because it may increase the risk of impingement. Assessment of the posterior shoulder can be done by measuring isolated glenohumeral internal rotation. To perform this test the humerus is taken into passive internal rotation while the scapular is stabilized by grasping the coracoid process and the spine and monitoring for movement (Fig. 3-6). When passive slack from the posterior shoulder is taken up, the humerus will no longer internally rotate or resistance to movement will allow the scapula to tilt forward. When motion is detected or internal rotation has ceased, the examiner measures isolated glenohumeral internal rotation. Wilk et al. (2009) have shown this to be moderately reliable, whereas Manske et al. using the same technique have proved excellent test–retest reliability (Manske et al. 2010). This motion should be compared bilaterally to assess for a deficit between involved and uninvolved shoulders. A difference of greater than 20 degrees of internal rotation is thought to be a precursor to shoulder pathology. Loss of shoulder internal rotation is not always pathologic because some of this motion may be lost as a result of bony changes in the humerus. The concept of total shoulder rotation ROM should also be mentioned. By adding the two numbers of GH internal rotation and external rotation together, a composite of total shoulder motion can be obtained (Fig. 3-7). Ellenbecker et al. (2002), measuring bilateral total rotation range of motion in professional baseball and elite junior tennis players, found that although a dominant arm may show increased external rotation and less internal rotation, the total ROM was not significantly different when comparing the two shoulders. Therefore, one needs to not only address the internal rotation loss, but also should ensure that the total range of motion is not limited. Using normative data from population specific research can assist the therapist in interpreting normal range of motion patterns and identify when sport-specific adaptations or clinically significant adaptations are present (Ellenbecker 2004).




Soon after soft tissue shoulder repairs passive motion may predominate. These passive ranges can be performed using Codman circumduction exercises, or passive motion can be gained by working with the therapist. Passive motions can be gained in all classical directions as long as there are no soft tissue limitations that need to be abided by. Other methods of gaining motion are through joint mobilizations from the therapist.


Passive and active assistive exercises initially begin with the patient in a supine position with the arm comfortably at the side with a small towel roll or cushion under the elbow and the elbow flexed. This position reduces the forces crossing the shoulder joint by decreasing the effect of gravity and shortening the lever arm of the upper extremity. As the patient begins to recover pain-free motion, the exercises can be progressed to sitting or standing.


Once active motion can be initiated, the patient is encouraged to work early on pain-free ranges below 90 degrees of elevation. For most patients an early goal is 90 degrees of forward flexion and approximately 45 degrees of external rotation with the arm at the side. For surgical patients, it is the responsibility of the surgeon to obtain at least 90 degrees of stable elevation in the operating room for the therapist to be able to gain this same motion after surgery. At this point in rehabilitation, methods to gain motion include active-assisted range of motion with wands or pulleys, passive joint mobilization, and passive stretching exercises (Figs. 3-8 and 3-9).





Pain Relief


Both shoulder motion and strength can be inhibited by pain and swelling, with pain being the major deterrent. Pain can be the result of the initial injury or from surgical procedures attempting to repair/replace the injured tissue. Pain relief can be achieved by a variety of modalities including rest, avoidance of painful motions (e.g., immobilization; Fig. 3-10), cryotherapy, ultrasound, galvanic stimulation, and oral or injectable medications (Fig 3-11). Previous literature substantiates that continuous cryotherapy following surgical procedures results in immediate and continued cooling of both subacromial space and glenohumeral joint temperatures (Osbahr et al. 2002) and decreases the severity and frequency of pain, which allows more normal sleep patterns and increases overall postoperative shoulder surgery comfort and satisfaction (Singh et al. 2001, Speer et al. 1996).





Muscle Strengthening


Appropriate timing for initiation of muscle strengthening exercises during shoulder rehabilitation is completely dependent on the diagnosis. A simple uncomplicated impingement syndrome may be able to commence strengthening exercises on day 1, whereas a postoperative rotator cuff repair may require up to 10 weeks before initiation of strengthening of the cuff, allowing the repaired tendon time to heal securely to bone of the greater tuberosity. Strengthening of the muscles around the shoulder can be accomplished through different exercises. Basic safe exercises include isometrics (Fig. 3-12), and closed kinetic chain exercises (Figs. 3-13 and 3-14). The advantage of closed chain exercises is a co-contraction of both the agonist and the antagonist muscle groups that help enhance stability of the glenohumeral joint. This co-contraction closely replicates normal physiologic motor patterns and function to help stabilize the shoulder and limit abnormal and potentially destructive shear forces crossing the glenohumeral joint. A closed chain exercise for the upper extremity is one in which the distal segment is stabilized against a fixed object. During shoulder exercises this stable object may be a wall, door, table, or floor. One example of a closed-kinetic-chain exercise used in an elevated, more functional position is the “clock” exercise in which the hand is stabilized against a wall or table (depending on the amount of elevation allowed) and the hand is rotated to different positions of the clock face (Fig. 3-13). This is done by creating an isometric contraction in the direction of the numbers around the clock face. Alternatively, the therapist can also give manual resistance in the same directions to the patient’s arm as they are stabilizing it by holding on to the wall (Fig. 3-14). These motions are thought to effectively stimulate rotator cuff activity. Initially, the maneuvers are done with the shoulder in less than 90 degrees of abduction or flexion. As healing tissues improve and motion is recovered, strengthening progresses to greater amounts of abduction and forward flexion.





Isometric exercises can also be performed in various ranges of shoulder elevation. It is easiest to do this with the patient in supine. The “balance position” is that of 90 to 100 degrees of forward flexion of the shoulder while supine (Fig. 3-15). This position requires little activation of the deltoid so that the rotator cuff can be worked without provoking a painful shoulder response. In this position a contraction from the deltoid will result in joint compression, helping to enhance joint stability. Rhythmic stabilization or alternating isometric exercises can be performed very comfortably in the supine position and can be done for both rotator cuff and shoulder muscles.



Strengthening of scapular stabilizers is important early on in the rehabilitation program. Scapular strengthening can begin in side lying with isometrics or isotonics or closed chain (Fig. 3-16) and progress to open-kinetic-chain exercises (Fig. 3-17).




Recovery can be enhanced by utilizing proprioceptive neuromuscular facilitation (PNF) exercises. The therapist can apply specific sensory inputs to facilitate a specific activity or movement pattern. One example of this is the D2 flexion–extension pattern for the upper extremity. During this maneuver, the therapist applies resistance as the patient moves the arm through predetermined patterns. These exercises can be done in various levels of shoulder elevation including 30, 60, 90, and 120 degrees of elevation. These exercises are to enhance the stability of the glenohumeral joint through a given active range of motion (AROM).


As the patient progresses, more aggressive strengthening can be instituted by moving from isometric and closed-chain exercises to those that are more isotonic and open chain in nature (Fig. 3-18). Open chain exercises are done with the distal end of the extremity no longer stabilized against a fixed object. This results in the potential for increased shear forces across the glenohumeral joint. Shoulder internal and external rotation exercises are done initially standing or seated with the shoulder in the scapular plane. The scapular plane position is recreated with the shoulder between 30 degrees and 60 degrees anterior to the frontal plane of the thorax, or halfway between directly in front (sagittal plane) and directly to the side (frontal plane). The scapular plane is a much more comfortable plane to exercise in because it puts less stress on the joint capsule and orients the shoulder in a position that more closely represents functional movement patterns. Rotational exercises should begin with the arm comfortably at the patient’s side and advance to 90 degrees based on the patient’s injury, level of discomfort, and stage of soft tissue healing. The variation in position positively stresses the dynamic stabilizers by altering the stability of the GH joint from maximum stability with the arm at the side to minimum stability with the arm in 90 degrees of abduction.



For those who participate in either competitive or recreational overhead sporting activities, the most functional of all open-chain exercises are plyometric exercises. Plyometric activities are defined by a stretch-shortening cycle of the muscle tendon unit. This is a component of almost all athletic activities. Initially the muscle is eccentrically stretched and loaded. Following the stretched position the shoulder/arm quickly performs a concentric contraction. These forms of exercises are higher level exercises that should only be included once the patient has developed an adequate strength base and achieved full ROM. Not all patients require plyometric training, and this should be discussed before their incorporation. Plyometric exercises are successful in development of strength and power. Theraband tubing, medicine ball training, or free weights are all acceptable plyometric devices for the shoulder (Fig. 3-19).



Nothing is more important when rehabilitating the shoulder than remembering the musculature of the upper extremity and core. Total arm strengthening is a must when rehabilitating the shoulder because injuries to the shoulder that limit normal functional movement patterns and use will result in strength deficits of other upper extremity muscles. Overall conditioning including stretching, strengthening, and endurance training of the other components of the kinematic chain should be performed simultaneously with shoulder rehabilitation.


Patient motivation is a critical component of the rehabilitation program. Without self-motivation, any treatment plan is destined to fail. For complete recovery, most rehabilitation protocols will require the patient to perform some of the exercises on his or her own at home. This requires not only an understanding of the maneuvers, but also the discipline for the patient to execute them on a regular basis. Patient self-motivation is even more crucial in the present medical environment with increased attention and scrutiny directed at cost containment. Many insurance carriers limit coverage for rehabilitation at the patient’s expense. As a result, a comprehensive home exercise program should be outlined for the patient early in the rehabilitation process. This allows patients to augment their rehabilitation exercises at home and gives them a feeling of responsibility for their own recovery.



Rotator Cuff Tendinitis in the Overhead Athlete


Michael J. O’Brien, MD, and Felix H. Savoie III, MD


The overhead throwing motion is a complex and intricate movement that places extraordinary demands and very high stresses on the shoulder joint complex. Therefore, the shoulder of an overhead athlete requires special consideration. It is a complex link in the kinetic chain that produces high-velocity overhead motion. Disruption of that kinetic chain by any means, whether by improper core strengthening, shoulder dyskinesia, poor mechanics, or poor posturing, places increased stress on the rotator cuff. Rotator cuff tendinitis and shoulder pain in the overhead athlete represent a unique challenge for the treating clinician in terms of both diagnosis and treatment. The key to successful management hinges on a thorough evaluation, correct diagnosis, and a structured multiphase rehabilitation protocol. Through a structured conditioning and rehabilitation program, many overhead athletes can return to play without being sidelined by surgery.


Overhead athletic activities can be classified as those movements that require repetitive motion with the arm in at least 90 degrees of forward flexion or abduction, or a combination of the two. Athletes who participate in activities such as swimming, gymnastics, volleyball, or throwing sports experience this type of repetitive overhead trauma and are prone to developing injuries to the shoulder joint complex. These athletes typically demonstrate a degree of hyperlaxity of the glenohumeral joint, resulting from increased laxity of the anterior joint capsule with concomitant tightness of the posterior capsule. Overhead athletes are able to function with this glenohumeral laxity by compensating with proper development of the dynamic stabilizers crossing the glenohumeral joint. The chief dynamic stabilizers are the rotator cuff, deltoid, and scapular stabilizing muscles.




Anatomy and Biomechanics


The rotator cuff is composed of four muscles: supraspinatus, infraspinatus, teres minor, and subscapularis. These four muscles take origin on the body of the scapula and insert on the tuberosities of the proximal humerus. The rotator cuff serves several functions in glenohumeral joint motion and stability. It provides joint compression, resistance to glenohumeral translation, and some rotation in all planes of motion. It is intricately involved in powering movement of the shoulder.







During overhead sports, extreme forces are placed on the rotator cuff. It is continuously challenged to keep the humeral head centered in the glenoid, preventing subluxations of the joint. If proper conditioning and sound mechanics are not used, the rotator cuff and posterior joint capsule can become inflamed and irritated. Chronic inflammation can become pathologic and lead to dysfunction of the rotator cuff. When the four cuff muscles fail to act in synchrony to keep the humeral head centered in the glenoid, dynamic stability can be compromised. Repeated microtrauma to the posterior rotator cuff and capsule leads to posterior capsule contracture. Posterior capsular tightness and loss of dynamic stability lead to increased subluxation and anterior–posterior (AP) translation of the humeral head on the glenoid, further contributing to irritation of the rotator cuff. Over time, this repetitive insult can cause tears of the rotator cuff and superior labrum.



The Throwing Cycle


The baseball pitch serves as the biomechanical model for many overhead throwing motions. The throwing cycle is a kinetic chain that derives energy from the lower extremities, transfers it through the pelvis and trunk rotation, and releases that energy through the upper extremity. The arm positions and motions of the throwing cycle serve as a good model for examination of rotator cuff function in overhead athletes. The throwing motion and its biomechanics have been divided into six stages: wind-up, early-cocking, late-cocking, acceleration, deceleration, and follow-through (Fig. 3-20).










Pathogenesis


Injury to the shoulder during the throwing cycle is thought to occur during the late-cocking phase, when the shoulder is in extreme external rotation and horizontal abduction. Abnormal motion of the humeral head relative to the glenoid can injure the superior and posterosuperior labrum and glenoid and the undersurface of the rotator cuff. This phenomenon has been called internal impingement of the shoulder or posterior superior glenoid impingement (Burkhart et al. 2003, Fleising et al. 1995, Jobe 1995, Kelly and Leggin 1999). Several factors have been implicated in the development of internal impingement, including traction on the biceps tendon, laxity of the anterior band of the inferior glenohumeral ligament caused by excessive external rotation, posterior capsular tightness, and scapular dyskinesia.





Muscle imbalance and capsular tightness contribute to rotator cuff pathology by allowing excess translation at the glenohumeral joint. Weakness of the supraspinatus or subscapularis can compromise compression of the glenohumeral joint during active shoulder motion. This, in turn, leads to increased translation across the joint.


Grossman et al. (2005) quantified glenohumeral motion following external rotation capsular stretch and subsequent posterior capsular shift to simulate a posterior capsular contracture in the thrower’s shoulder. In maximal external rotation in intact specimens, the humeral head moved in a posterior and inferior direction. A posterior capsular shift was performed to simulate posterior capsular contracture. Following posterior capsular shift, there was a trend toward a more superior position of the humeral head in maximal external rotation. Posterior capsular contracture causes a similar result as the head is pushed anterior–superior into the coracoacromial arch during flexion. Superior translation allows the head to migrate closer to the acromion, and an increase in the force transmitted to the rotator cuff results as the cuff is pressed between the humeral head and the overlying coracoacromial arch. The increased pressure on the cuff can lead to degradation and damage over time.



History and Physical Examination


Evaluation of overhead athletes, particularly at higher levels, should begin prior to the season and continue intermittently throughout the season. Subjective complaints regarding performance often precede complaints of pain in the shoulder or elbow. Common complaints include loss of command or control of the pitch, loss of pitching velocity, a subtle change in pitching mechanics, or even discomfort distant to the throwing arm. Early identification of these problems requires open communication among players, coaches, physicians, and athletic trainers.






Physical examination of the overhead athlete requires a global evaluation.





The physical examination of the shoulder and upper extremity should always begin with inspection.




Active and passive range of motion (PROM) should be assessed and compared to the contralateral side. The American Shoulder and Elbow Surgeons have recommended four functional ranges of motion that should be measured (Richards et al. 1994): forward elevation, internal rotation, and external rotation at the side and at 90 degrees of abduction are measured. Loss of the total arc of rotation, specifically with internal rotation, is a common finding in the glenohumeral joint of the injured pitcher (Burkhart et al. 2003). This loss is likely secondary to tightness of the posterior soft tissues, including the posterior rotator cuff and capsule.


Complete assessment of the shoulder should also include careful assessment of rotator cuff strength and glenohumeral joint laxity and provocative tests to identify intra-articular, subacromial, and acromioclavicular pathology.







Management


Frequently, rotator cuff tendinitis in the overhead athlete can be successfully treated with a well-structured and carefully implemented nonoperative rehabilitation program (Rehabilitation Protocol 3-1). Rehabilitation follows a multiphase approach with emphasis on controlling inflammation, restoring muscle balance, improving soft tissue flexibility, enhancing proprioception and neuromuscular control, and efficiently returning the athlete to competitive throwing (Wilk et al. 2002). Treatment should focus on restoration of sound mechanics during the throwing cycle, core muscle strengthening of the trunk and lower extremities, and strengthening of periscapular stabilizers.












REHABILITATION PROTOCOL 3-1 Rehabilitation for Rotator Cuff Tendinitis in Overhead Athletes



Phase I






Phase I strengthening exercises using elastic bands, or free weights of 1 to 4 pounds, can also be initiated in this early phase. Elastic bands may be easier to use and are more portable for the patient to use at home. The patient can exercise with the bands in the erect position and better integrate the scapular muscles.





Phase III


At this point, ROM should be full and pain free. Athletes will progress to higher-level exercises involving functional combination movements in more provocative positions. Patients who must repetitively function with the arm at or above shoulder level should be exercised into those positions.








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Jun 22, 2016 | Posted by in PHYSICAL MEDICINE & REHABILITATION | Comments Off on Shoulder Injuries

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