Rotator cuff tendinopathy

INTRODUCTION — Shoulder pain is a common complaint in the primary care setting and sports medicine clinics. Patients with rotator cuff tendon pathology comprise a sizeable portion of this subpopulation. A basic understanding of the anatomy and pathophysiology of the rotator cuff tendons will help the clinician evaluate these patients.

The clinical pathophysiology, diagnosis, and management of rotator cuff tendinopathy are reviewed here. The general evaluation of the patient with shoulder pain, the shoulder examination, other specific shoulder problems (including rotator cuff tear), and general treatments for tendinopathy are discussed separately. (See "Evaluation of the adult with shoulder complaints" and "Physical examination of the shoulder" and "Overview of the management of overuse (persistent) tendinopathy" and "Presentation and diagnosis of rotator cuff tears" and "Rehabilitation principles and practice for shoulder impingement and related problems".)

TERMINOLOGY — Knowledge of the pathogenesis of tendon overuse disorders remains incomplete. Histopathological, biochemical, and molecular studies reveal a degenerative process with little evidence of inflammation, although inflammation may play a role initially, and inflammation following an acute injury can occur concomitantly with chronic tendon pathology. The pathophysiology of chronic tendon disorders is discussed separately. (See "Overview of overuse (persistent) tendinopathy".)

The term "tendinitis" came into common parlance to describe chronic painful tendon injuries before the underlying pathology was better understood. The terms "tendinosis" or "tendinopathy" may better describe chronic tendon disorders. Despite support for the term "tendinopathy" among experts, the term "tendinitis" is deeply ingrained in clinical practice and the historical literature. In this review, we use the term "tendinopathy" to refer to symptomatic primary rotator cuff tendon disorders.

EPIDEMIOLOGY — The incidence of shoulder complaints is approximately 11.2 cases per 1000 patients per year [1]. Shoulder pain occurs more often in older adults [2,3]. In working populations, the incidence of shoulder-related symptoms may be as high as 14 to 18 percent [4]. (See "Evaluation of the adult with shoulder complaints".)

The prevalence of rotator cuff disease, symptomatic or asymptomatic, that is identified by surgery or imaging increases with age from 9.7 percent under age 20 to 62 percent over age 80 [5]. Rotator cuff disorders are a significant source of morbidity among manual laborers and those whose work involves a great deal of repetitive motion [4,6-8]. In the general population as well, rotator cuff disease is the most common cause of shoulder pain [1,3,4,6,9,10]. Any of the rotator cuff tendons may be involved, but the supraspinatus tendon is most frequently injured.

Rotator cuff disease is often described in overhead athletics. Although there is a paucity of high-quality, sport-specific studies examining the prevalence of rotator cuff tendinopathy, observational evidence supports the clinical correlation between overhead sport and shoulder pain, specifically rotator cuff pathology [11-14]. Sports associated with rotator cuff tendon injury include baseball [15], tennis [11], swimming [12], golf [13], and men's gymnastics [14]. Based on such observational data and the authors' experience, repetitive, sport-specific movements that create subacromial compression or result in dynamic eccentric load of the rotator cuff often lead to pain and pathology of the rotator cuff tendons. Examples of such movements include pitching in baseball or cricket and serving in tennis. (See 'Pathophysiology and mechanism of injury' below.)

RISK FACTORS — Repetitive overhead activity, whether in sport or work, is a major risk factor for rotator cuff tendinopathy [1,16]. Other risk factors include anatomic variants that predispose to rotator cuff impingement, scapular instability or dyskinesis, and older age [17-20]. In the working population, problems in one shoulder can place the contralateral shoulder at risk [4]. There is preliminary evidence for genetic or familial predisposition to rotator cuff disease [21]. (See "Subacromial (shoulder) impingement syndrome".)

Athletes who perform overhead activity, such as swimming, tennis, throwing, golf, weightlifting, volleyball, and gymnastics, are at risk. Within sport-specific overhead activities, several biomechanical factors have been linked to rotator cuff disease, including internal rotation deficits, glenohumeral instability, scapular dyskinesis, improper scapula positioning, faulty posture, unstable torso (ie, weak core musculature), and poor rotator cuff muscle endurance [22,23]. However, some research has raised questions about whether some of these factors, such as glenohumeral instability, internal and external range of motion imbalances, and improper scapular positioning, contribute to or are caused by rotator cuff pathology [24].

Weakness of the rotator cuff muscles or secondary supporting muscles (eg, scapular stabilizers), or fatigue of these muscles during sport, is common and can lead to poor mechanics and dysfunction of the shoulder. Instability or hypermobility of the glenohumeral joint unrelated to muscle weakness also predisposes to rotator cuff injury [6,25].

Flawed postural alignment and scapular mechanics are important contributors to rotator cuff disease. An objective measure of postural alignment as it relates to such disease is the critical shoulder angle (CSA). CSA is the angle between the plane of the glenohumeral fossa and the inferolateral border of the acromion (image 1). A higher angle is associated with increased loads placed on the rotator cuff [26,27].

Clinically, we observe a higher prevalence of rotator cuff disease in patients with co-existing degenerative disease of the cervical spine. This association has been reported in an observational study of patients treated surgically for degenerative disease of the cervical spine [28]. The association was higher among patients with lower cervical spine disease (C4 to T1).

An increased risk for rotator cuff tendinopathy has been reported for certain chronic diseases, including obesity, diabetes, and hyperlipidemia [29,30]. Statin therapy may attenuate the risk among patients with hyperlipidemia [30].

CLINICAL ANATOMY — The clinical anatomy of the shoulder is discussed in detail separately (figure 1A-C). (See "Evaluation of the adult with shoulder complaints", section on 'Anatomy and biomechanics'.)

BASIC BIOMECHANICS — Clinically relevant shoulder motions involving the glenohumeral and scapulothoracic joints are more complex than previously appreciated [6]. Nevertheless, the function of the rotator cuff is relatively easy to understand and provides the basis for clinical testing. The biomechanics of throwing are reviewed separately. (See "Throwing injuries: Biomechanics and mechanism of injury".)

Rotator cuff tendon pathology most often involves damage to the supraspinatus tendon. The supraspinatus muscle assists in abduction and external rotation of the shoulder. Researchers have tried to identify accurate clinical methods of assessing supraspinatus function [6]. According to one approach, the function of the supraspinatus can be tested in relative isolation with the arm abducted in the scapular plane (approximately 30 degrees of forward flexion) and the shoulder in full internal rotation (the so-called "empty can" position (picture 1)) [31]. Despite these efforts, it appears that supraspinatus function cannot be tested in isolation because of the inextricable role of other shoulder muscles in abduction and external rotation [32,33].

The infraspinatus muscle assists in external rotation and abduction of the shoulder. It is assisted in these motions by the deltoid, teres minor, and supraspinatus. Although some researchers advocate specific assessment techniques, attempts at isolating infraspinatus function for clinical testing have proven difficult [1,34]. The infraspinatus is commonly tested by having the patient isometrically resist external rotation with the elbow flexed at 90 degrees in a neutral rotation (picture 2). This is thought to limit the assistance of the deltoid and supraspinatus.

The teres minor muscle also assists in external rotation and abduction of the shoulder. Electromyography (EMG) studies indicate that the teres minor is especially active in external rotation when the arm is abducted to 90 degrees [34]. Biomechanical studies suggest that the teres minor contributes up to 45 percent of the power of external rotation. With hypertrophy, the teres minor can exhibit sufficient strength to compensate for tears in the infraspinatus that might otherwise manifest during testing of external rotation against resistance [3].

The subscapularis muscle's primary function is to internally rotate the shoulder, but it also assists in abduction and adduction. EMG studies show that the pectoralis major, latissimus dorsi, and teres major assist in internal rotation and may confound clinical testing of the subscapularis [6,7]. The subscapularis tendon helps to stabilize the long head biceps tendon, and tears of the subscapularis can be associated with biceps tendon injuries. (See "Biceps tendinopathy and tendon rupture".)

In addition to its motor functions, the rotator cuff compresses the humoral head in the glenoid fossa, thereby stabilizing the glenohumeral joint. By means of this compression, the rotator cuff counterbalances the elevating forces of the deltoid as well as the forces of other muscles acting on the humerus [35,36]. Weakness of the rotator cuff can lead to superior subluxation of the humeral head when the shoulder is abducted beyond 90 degrees, predisposing to impingement syndromes. (See "Subacromial (shoulder) impingement syndrome".)

PATHOPHYSIOLOGY AND MECHANISM OF INJURY — Several explanations for the pathophysiology of rotator cuff tendinopathy have been proposed. Early research expounded two theories of rotator cuff tendinopathy: one emphasized biomechanical factors (extrinsic), and the other emphasized vascular factors (intrinsic) [6,17,31,32,37]. It was thought that elements of both play a role.

●Intrinsic mechanism – This mechanism emphasizes injury within the tendon from tendon overload, degeneration, or other insult [6,17,31,32]. A compromised microvascular system compounds the problem by creating a "critical zone" of avascularity at the site of injury.

Tensile overload during eccentric contraction (ie, muscle contracts while lengthening) with overhead activity is implicated in this mechanism. This is particularly true for the overhead athlete. As an example, when a pitcher's throwing arm decelerates after release of the ball, the lengthening posterior rotator cuff muscles contract to slow the arm. This eccentric contraction places a large tensile load on the posterior rotator cuff. (See "Throwing injuries: Biomechanics and mechanism of injury".)

Age and comorbidity can play a role in this mechanism. Aging tendons develop microtears, calcification, and fibrovascular proliferation. Comorbidities (eg, diabetes mellitus, rheumatoid arthritis, Marfan or Ehlers-Danlos syndromes) can contribute to tendon pathology. (See "Overview of the musculoskeletal complications of diabetes mellitus".)

●Extrinsic mechanism – This mechanism emphasizes the role of compressive forces exerted by surrounding structures in causing rotator cuff injury [6,17,31]. Various structures may impinge the rotator cuff, including the acromion, the coracoacromial ligaments, the coracoid process, and the acromioclavicular joint with osteoarthritic changes on its undersurface (figure 1A-C). Glenohumeral instability can also lead to secondary compressive forces. The mechanics of such impingement are discussed separately. (See 'Basic biomechanics' above and "Subacromial (shoulder) impingement syndrome".)

Subsequent research has proposed additional or alternative explanations for rotator cuff tendinopathy. One is the "continuum model of tendon pathology" [38]. This model involves three stages: reactive tendinopathy (a proliferative response due to tensile overload), tendon disrepair (disorganized cellular response), and degenerative tendinopathy (irreversible pathological change). Another model proposes three primary insults to the tendon cell that may contribute to pathology [39]:

●Tenocyte overstimulation

●Collagen disruption

●Inflammation

Regardless of which insult is primarily involved, a significant cellular response occurs. The complexities of tendon structure and function play a role. (See "Overview of overuse (persistent) tendinopathy", section on 'Pathology and terminology'.)

Complicating these models of tendon pathophysiology is the difficulty correlating changes in tendon structure identified in imaging studies with the variability in individual patient symptoms. Some patients experience considerable pain from acute tendinitis despite minimal structural change on imaging studies, while others experience little or no pain from chronic tendinopathy despite significant changes in tendon appearance [38,39]. (See 'Diagnostic imaging' below.)

CLINICAL PRESENTATION AND EXAMINATION — A careful evaluation of the history and physical examination, supplemented by musculoskeletal ultrasound wherever available, is necessary to diagnose rotator cuff tendinopathy; no single examination finding or test can reliably establish the diagnosis [40].

Clinical presentation — Patients with rotator cuff tendinopathy complain of shoulder pain with overhead activity. Painful daily activities may include putting on a shirt or brushing hair. Patients may localize the pain to the lateral deltoid and often describe pain at night, especially when lying on the affected shoulder. The history often reveals risk factors. (See 'Epidemiology' above.)

Overhead athletes often complain of pain while performing their sport (eg, pitching, freestyle swimming), weakness, or a decline in performance. Reduced performance generally manifests as diminished speed, accuracy (eg, when pitching or serving), or endurance.

Physical examination — Performance of the shoulder examination is discussed in detail separately (see "Physical examination of the shoulder"). The portions of this examination of particular relevance to rotator cuff pathology are discussed briefly below. One small trial found that a battery of carefully performed physical examination tests for rotator cuff tendinopathy failed to diagnose a number of pathologic conditions identified readily by ultrasound [41]. For clinicians skilled in musculoskeletal ultrasound, it is an important tool for diagnosis. (See 'Musculoskeletal ultrasound' below and "Musculoskeletal ultrasound of the shoulder".)

Overall, examination techniques for rotator cuff pathology are moderately sensitive, but no single examination finding or provocative maneuver is pathognomonic for rotator cuff tendinopathy [40]. In part, this is due to the dearth of large, prospective studies using consistent standards for performance and interpretation of examination maneuvers [42].

Notable examination findings consistent with rotator cuff tendinopathy are described below:

●Inspection

Muscle atrophy – With long-standing rotator cuff tendinopathy, atrophy of supraspinatus and infraspinatus muscles may be present. A sunken appearance is appreciable in the corresponding scapular fossa (picture 3).

Scapula appearance and motion – The scapula of the affected shoulder may demonstrate abnormal appearance and motion compared with the unaffected side. Deviation of the resting position of the scapula or abnormal scapular motion is referred to as scapular dyskinesis and often can be appreciated by observation and comparison with the contralateral shoulder, assuming it is healthy.

In athletes, scapula asymmetries may be subtle and dynamic. The strength of many athletes may allow for compensation, producing normal-appearing scapular movement during a single shoulder abduction. However, repetitive forward flexion and abduction, or a closed-chain push-up motion, may accentuate asymmetries. (See "Physical examination of the shoulder", section on 'Scapulothoracic motion and strength'.)

●Neck examination – Shoulder pain may be referred from the neck. It is important to examine the neck and perform a screening neurologic examination to rule out cervical spine pathology. Neck findings associated with serious pathology are summarized in the table (table 1). (See "Evaluation of the adult patient with neck pain".)

●Palpation – Rotator cuff tendinopathy often creates tenderness over the affected musculature (supraspinatus, infraspinatus) or focal subacromial tenderness at the lateral or posterior-lateral border of the acromion. However, the location of the rotator cuff deep to the deltoid makes palpation difficult and unreliable, particularly in well-muscled athletes. There may be tenderness at the supraspinatus tendon insertion, but the sensitivity and specificity of this maneuver are unknown. A false negative (nontender) may occur due to the rotator cuff injury lying deep to the deltoid or a false positive (tender) may occur due to deltoid injury or associated myofascial pain in the region of the rotator cuff muscle belly. (See "Physical examination of the shoulder", section on 'Palpation'.)

●Range of motion – Range of motion testing can be performed solely on the side of the painful extremity or bilaterally. The authors prefer a simultaneous bilateral technique. This helps to differentiate deficiencies from the patient's baseline motion.

Pain with greater than 90 degrees of shoulder abduction or with internal rotation suggests rotator cuff tendinopathy (picture 4). Painful arc testing demonstrates greater specificity than sensitivity and is most useful when used in conjunction with the Neer (picture 5) and Hawkins-Kennedy (picture 6) tests, which demonstrate better sensitivity (see discussion of "Special tests" just below). Pain that occurs between 60 and 120 degrees of active abduction marks a positive arc test. Abduction is performed with the arm at 30 degrees of horizontal adduction (ie, in the plane of the scapula). With rotator cuff pathology, passive range of motion is usually greater than active range of motion. (See "Physical examination of the shoulder", section on 'Range of motion'.)

●Strength testing – Supraspinatus strength is evaluated by performing the "empty can" (or Jobe strength) test (picture 1). External rotation (infraspinatus) strength of the shoulder can be tested with the patient's arms at their sides and the elbows in 90 degrees of flexion (picture 2). Alternatively, external rotation can be tested against resistance with the shoulder abducted to 90 degrees and the elbow flexed to 90 degrees (hornblower sign). The push-off (or Gerber lift-off) test can be used to assess internal rotation (subscapularis) strength (picture 7). Performance of these maneuvers is described in greater detail separately. (See "Physical examination of the shoulder", section on 'Examination for rotator cuff pathology'.)

●Special tests – The Neer and Hawkins-Kennedy tests are commonly used to diagnose impingement (picture 5 and picture 6). (See "Physical examination of the shoulder", section on 'Special tests for shoulder impingement'.)

Clinicians may want to perform an acromioclavicular compression (picture 8 and picture 9) or crossover (picture 10) test. This test may be positive due to acromioclavicular joint or rotator cuff pathology and therefore is most useful for ruling out acromioclavicular injury when negative. (See "Acromioclavicular joint injuries ("separated" shoulder)", section on 'History and examination'.)

●Lidocaine injection test – A subacromial injection of lidocaine can be used to alleviate pain and to distinguish between rotator cuff tendinopathy and tear. Examination with adequate analgesia following injection provides a more accurate assessment of muscle strength. Patients with tendinopathy exhibit normal strength once pain is relieved; those with a large tear manifest persistent weakness. (See "Presentation and diagnosis of rotator cuff tears".)

DIAGNOSTIC IMAGING

Plain radiographs — Routine plain radiographs of the shoulder do not reveal signs of rotator cuff tendinopathy and are generally not indicated in patients suspected of having such injuries. Plain films can be helpful to identify co-existing conditions or predisposing factors and may be useful in the following clinical situations:

●Assessment when there is no response to conservative therapy and other pathology is suspected (eg, acromioclavicular joint arthritis, glenohumeral joint arthritis, tendon calcification)

●Recurrent rotator cuff tendinopathy

●Anatomical evaluation prior to subacromial or glenohumeral joint injection (not essential prior to injection; ultrasound-guided injection may be more useful)

Musculoskeletal ultrasound

Utility and test characteristics — Many clinicians consider musculoskeletal ultrasound to be the gold standard for the initial evaluation of tendon disorders, including rotator cuff disease [43,44]. Musculoskeletal ultrasound enables the trained clinician to evaluate tendons while they are in motion and to compare them with the contralateral shoulder at the bedside. Clinicians can then correlate the ultrasound and physical examination findings. Other advantages include ease of use, absence of radiation exposure, and relative low cost [43]. However, skillful performance of the musculoskeletal ultrasound requires specific training and regular practice.

Multiple studies demonstrate ultrasound's high sensitivity in diagnosing rotator cuff disease, particularly complete tendon tears [44-51]. In a systematic review of studies comparing the diagnostic accuracy for ultrasonography, magnetic resonance imaging (MRI), and magnetic resonance arthrography for rotator cuff pathology, five studies (311 shoulders) of good quality using operative findings as the gold standard reported the sensitivity and specificity of ultrasound for tendinopathy to be 79 and 94 percent, respectively [50]. New ultrasound techniques such as strain elastography may improve diagnostic accuracy, but further research is needed [52].

Musculoskeletal ultrasound has limitations. Even in experienced hands, it can be difficult to visualize the entire rotator cuff in some patients, and this may reduce sensitivity and specificity for identifying rotator cuff pathology.

Pathologic findings — Changes noted on ultrasound diagnostic for rotator cuff pathology may include [41,53]:

●Tendon hypoechogenicity or thickening with or without internal hypo- or hyperechoic foci (image 2)

●Tendon retraction (image 3)

●Calcifications (image 4)

●Fibrillar disruptions (image 5)

●Fatty infiltration

●Impingement during dynamic examination

The supraspinatus tendon is involved most often. Neovascularization, which is seen in other pathologic tendons, is nondiagnostic when found within the rotator cuff tendons [54]. Scales for categorizing and grading ultrasound signs of tendinopathy have been developed, but none is universally accepted [55].

Performance of examination — Performance of the musculoskeletal ultrasound examination of the shoulder, including a detailed description of how to examine the rotator cuff, is provided separately. Guidance to help clinicians who perform ultrasound examinations with challenging aspects of the evaluation of rotator cuff tendinopathy is provided below. (See "Musculoskeletal ultrasound of the shoulder".)

Visualization of the rotator cuff tendons requires proper patient positioning (Crass position), appropriate sonographic settings, proper transducer placement, and dynamic maneuvers to provide the best views. For most patients, we use a linear transducer with a frequency of 10 MHz and focal zone approximately 2 cm deep. We adjust the focal zone to accommodate the patient's body habitus. Achieving the ideal Crass or modified Crass position to examine the supraspinatus can be difficult for some patients in pain. We find that we can coax most into the necessary position by having them simulate reaching for a wallet in their back pocket with their palm facing forward, and then asking them to sit back on their hand, using their body weight to help maintain the position.

Once the probe is in the optimal orientation, the examiner can gently adjust the position using basic probe movements (eg, tilt, toe-in, toe-out, glide, and rotation) to identify the desired tendon and assess for anisotropy. To validate tendon pathology, the examiner should corroborate findings in both long-axis and short-axis views.

Determining tendon anechogenicity or hypoechogenicity from anisotropy requires careful attention to probe placement. Virtually all tendons curve and thus are subject to anisotropy at some probe position. The examiner should make frequent adjustments (eg, toeing) in order to examine as much of the tendon as possible. The best images are acquired with the probe perfectly perpendicular to the target. As an example, the subscapularis tendon is oriented deep to superficial, moving medial to lateral. Thus, it is best to toe in the medial edge of the probe to optimize the image. Generous use of ultrasound gel helps to improve image quality.

Additional ultrasound resources — Instructional videos demonstrating proper performance of the ultrasound examination of the shoulder and related pathology can be found at the website of the American Medical Society for Sports Medicine. Registration must be completed to access these videos, but no fee is required.

Magnetic resonance imaging — MRI is used to rule out rotator cuff tear when conservative therapy fails, to assess for tear suspected on clinical grounds, and to aid in diagnosis when shoulder pathology is unclear. Injuries to the labrum, glenohumeral joint, and other adjacent structures can be identified by MRI. MRI can also be used when diagnostic confirmation is needed to guide the patient's return to sport. The diagnosis of rotator cuff tear is discussed separately. (See "Presentation and diagnosis of rotator cuff tears".)

MRI findings must be interpreted in clinical context, as asymptomatic tears are common. An observational study of MRI performed in 96 asymptomatic individuals showed rotator cuff tears in 34 percent overall and 54 percent of patients over 60 years of age [19].

High-quality data describing the sensitivity and specificity of MRI for rotator cuff tendinopathy is not available. In a systematic review of studies comparing the diagnostic accuracy for ultrasonography, MRI, and magnetic resonance arthrography for rotator cuff pathology, all three techniques showed high sensitivity and specificity for full-thickness rotator cuff tears, but sensitivity for partial tears was low; and for tendinopathy, data were available for ultrasound only [50]. Extrapolating from this data, it is best to assume that the sensitivity of MRI for rotator cuff tendinopathy is not high. Rotator cuff degeneration is associated with a high-intensity signal on MRI [34].

New MRI techniques are emerging that may diagnose rotator cuff pathology with greater accuracy. As an example, MRI T2 mapping may be useful for distinguishing tendinopathy from tear [56].

DIFFERENTIAL DIAGNOSIS — Rotator cuff tendinopathy may be a manifestation of shoulder impingement but must be distinguished from other causes of shoulder pain (table 2 and algorithm 1 and table 3). A detailed discussion of the differential diagnosis and clinical assessment of shoulder pain is found separately. (See "Subacromial (shoulder) impingement syndrome" and "Evaluation of the adult with shoulder complaints".)

In particular, it is important to distinguish rotator cuff tendinopathy from cervical radiculopathy, acromioclavicular osteoarthritis, subacromial bursitis, bicipital tendinopathy, rotator cuff tear, glenoid labrum tear, and adhesive capsulitis [17].

DIAGNOSIS — The diagnosis of rotator cuff tendinopathy is typically made clinically based upon a history of gradual, atraumatic shoulder pain at rest that is made worse by overhead activities such as throwing. Night pain is often present. Positive results from provocative maneuvers, particularly the Hawkins-Kennedy, Neer, and Jobe tests, are highly predictive. Imaging is not always necessary, but musculoskeletal ultrasound can confirm the diagnosis in many cases. Definitive diagnosis entails arthroscopic or open surgical assessment, which is rarely necessary.

INDICATIONS FOR ORTHOPEDIC REFERRAL

General indications for referral — Many options are available for the management of rotator cuff tendinopathy. We believe that every effort should be made to use nonsurgical treatment (in particular, a properly designed and implemented physical therapy program) before seeking orthopedic surgery referral. Such referral is indicated only after an appropriate period, generally at least six months, has demonstrated that nonoperative care has been ineffective, or in cases where shoulder function worsens during the course of appropriate nonsurgical treatment. (see "Rehabilitation principles and practice for shoulder impingement and related problems").

A systematic review of six practice guidelines identified the following general criteria given for surgical referral [57]:

●Functional deficits that interfere with activities of daily living

●Persistent pain

●Worsening function

●Persistent activity limitations that prevent participation in desired activities or work

The timeframe for referral among guidelines varied from as little as six weeks to as long as six months. Using these general criteria as a framework, we individualize referral decisions based on the known pathology, progress with current treatment, and patient goals.

In addition to failed rehabilitation, significant complications of rotator cuff tendinopathy may warrant referral to orthopedic surgery. Tendinopathy complicated by a severe tendon tear causing disability or significant pain is one example. In addition, pain associated with rotator cuff tendinopathy may cause a patient to restrict the movement of their shoulder, ultimately leading to adhesive capsulitis (frozen shoulder). Patients who have developed adhesive capsulitis from longstanding rotator cuff disease that is refractory to conservative therapy may need orthopedic referral. Indications for orthopedic referral and the overall management of rotator cuff tears and frozen shoulder are discussed separately. (See "Frozen shoulder (adhesive capsulitis)" and "Management of rotator cuff tears".)

Limitations of surgery — Surgery may offer benefit in some cases, but it is worth noting that some orthopedic procedures commonly used to treat rotator cuff tendinopathy lack support from well-controlled studies and do not appear to be effective. As an example, subacromial decompression is often used to treat rotator cuff tendinopathy. In theory, this procedure provides more space for a thickened, painful tendon, but studies have not borne out its effectiveness.

A 2019 systematic review of eight randomized trials involving 1062 patients with rotator cuff disease involving shoulder impingement found no clinically or statistically significant differences in pain reduction, shoulder function, or health-related quality of life at up to one year follow-up in patients treated with and without subacromial decompression. Two of these trials, involving 506 patients, compared arthroscopic subacromial decompression with arthroscopy without decompression (placebo surgery) and reported no difference in patient-important outcomes. Both trials were judged to be at very low risk of bias and in both each patient group performed physical therapy following their respective procedure. The authors of the systematic review concluded that "subacromial decompression for painful rotator cuff disease does not provide clinically important benefits" [58]. This conclusion appears to hold true for longer-term results. As an example, in a randomized trial with a mean follow-up of 12 years, no significant differences in pain, disability, or function were found between patients treated with arthroscopic subacromial decompression and physical therapy and those treated with physical therapy alone [59].

Some have challenged the criticisms leveled at subacromial decompression citing methodologic problems in some trials, such as lack of long-term follow-up and crossover from nonsurgical to surgical study populations [60]. Subacromial decompression has been performed to treat several different conditions and different stages of disease. An important problem may be the lack of clear indications. One surgeon has proposed a list of possible indications for subacromial decompression, including six months of significant, unremitting pain with overhead activities or at night and radiologic evidence of mechanical impingement (eg, sclerosis, bone cysts, or osteophytes at the greater tuberosity and anterior acromial spurs) with no evidence of a severe partial or complete rotator cuff tear on advanced imaging [60].

OUR APPROACH TO EVALUATION AND MANAGEMENT — The clinical diagnosis of rotator cuff tendinopathy can be difficult, particularly if the clinician is not skilled in musculoskeletal ultrasound. We approach patients with suspected rotator cuff pathology in the manner described here but recognize that alternative approaches may be reasonable. A management algorithm outlining our approach is provided (algorithm 2).

We begin with a focused history and physical examination (see 'Clinical presentation and examination' above). The examination includes the following:

●Complete neck examination (see "Evaluation of the adult patient with neck pain", section on 'Evaluation')

●Inspection for rotator cuff atrophy (picture 3)

●Evaluation of range of motion (including painful arc testing), encompassing both passive and active range of motion

●Rotator cuff strength testing (including drop arm test (movie 1) and external rotation strength testing (picture 2) for rotator cuff tear)

●Specialty testing (including the Neer (picture 5) and Hawkins-Kennedy (picture 6) tests)

●Bedside musculoskeletal ultrasound, if the technology is available and the examiner proficient (see "Musculoskeletal ultrasound of the shoulder")

If we suspect a clinically significant rotator cuff tear based on the history and examination (eg, discrete history of trauma, weakness that impairs function), we either obtain magnetic resonance imaging (MRI) or make prompt referral to an orthopedic surgeon. We maintain a lower threshold for referral in the case of high-functioning athletes. If we suspect a rotator cuff tear but the patient has minimal weakness and reasonable motion, we generally embark on a course of nonsurgical management. (See "Presentation and diagnosis of rotator cuff tears" and "Management of rotator cuff tears".)

If we suspect rotator cuff tendinopathy, we initiate conservative medical management, which includes the following:

●Cryotherapy (for acute injuries) (see 'Basic initial care' below)

●Relative rest (avoid aggravating activities)

●Nonsteroidal antiinflammatory drugs (NSAIDs) for 7 to 10 days

●Physical therapy (see 'Physical therapy' below)

The duration and success of physical therapy depends upon many factors, including the chronicity and severity of the tendinopathy, compliance with treatment, and the appropriateness of the program prescribed. We believe that whenever possible, it is important for patients to begin rehabilitation under the guidance of a knowledgeable professional (eg, athletic trainer or physical therapist with experience managing rotator cuff injury). The timing of follow-up is discussed below. (See 'Follow-up care' below.)

If function and symptoms improve over several weeks of physical therapy, we have the patient continue therapy and begin a gradual, stepwise resumption of activities, including sports. If therapy is not successful, or pain limits the ability to perform the prescribed exercise regimen, we may give a single glucocorticoid injection in the hope that short-term relief of symptoms will enable the patient to continue physical therapy. Topical nitroglycerin may be a useful adjunct treatment if symptoms persist.

Should function fail to improve despite adequate rehabilitation, we obtain imaging studies. Musculoskeletal ultrasound, if not performed previously, is obtained first. We perform a plain radiograph for persistent symptoms to assess for anatomic variants, such as a downsloping acromion or os acromiale, and acromioclavicular or glenohumeral osteoarthritis. We obtain an MRI if the musculoskeletal ultrasound is nondiagnostic, a rotator cuff tear is suspected, or the diagnosis remains unclear. (See 'Diagnostic imaging' above.)

Subsequent management depends upon the results of imaging studies. Alternative diagnoses are managed accordingly, and clinically significant rotator cuff tears are referred to an orthopedic surgeon. For rotator cuff tendinopathy, we continue conservative management. Physical therapy may require several months before adequate shoulder function is achieved. We refer the patient to an orthopedic surgeon if, after six to nine months of conservative treatment, patient function and symptoms fail to improve substantially. (See 'Indications for orthopedic referral' above.)

TREATMENTS — Many treatments for rotator cuff tendinopathy exist, but few are supported by strong scientific evidence. Below is a discussion of the general management of rotator cuff tendinopathy. Our suggested approach to the evaluation and management of rotator cuff tendinopathy is described above and summarized in the following algorithm (algorithm 2); a general discussion of treatments for tendinopathy is provided separately. (See 'Our approach to evaluation and management' above and "Overview of the management of overuse (persistent) tendinopathy".)

Basic initial care — Initial therapy for rotator cuff tendinopathy consists of ice (if there is acute injury), rest, and nonsteroidal antiinflammatory drugs (NSAIDs) [6,17]:

●Cryotherapy (ice) – Despite a dearth of scientific research, cryotherapy is generally believed to decrease acute swelling and inflammation of the rotator cuff and adjacent bursae and to provide some analgesia [31,61]. Cryotherapy may also improve isometric strength in the acute phase of injury. Ice may be especially effective when tendinopathy is associated with surrounding inflammation [34].

●Relative rest (activity modification) – Rest means avoiding activities that aggravate symptoms, including all overhead activities.

●NSAIDs – For acute injuries, we give a short course (ie, 7 to 10 days) of scheduled NSAID therapy. Thereafter, patients may use an NSAID for occasional analgesia if they find the medication effective. Effective analgesia helps patients perform rehabilitation exercises.

The use of NSAIDs for tendinopathy remains controversial [31,34]. During the period of acute injury, debate continues about whether blocking the inflammatory response inhibits healing. In the treatment of chronic tendinopathy, it is unclear what benefit NSAIDs provide without evidence of an inflammatory process. (See 'Pathophysiology and mechanism of injury' above.)

A review of 32 studies addressing the benefit of NSAIDs in tendinopathy identified only nine prospective, placebo-controlled trials [31]. Of these nine studies, five found some analgesic effect from NSAIDs; no study assessed tendon healing. A subsequent systematic review of 12 studies of limited quality concluded that NSAIDs provide short-term pain relief equivalent to injected glucocorticoid but no functional benefit [62]. Topically applied NSAIDs may improve pain in some musculoskeletal conditions but have not been studied in rotator cuff tendinopathy. (See "Overview of the management of overuse (persistent) tendinopathy", section on 'Nonsteroidal antiinflammatory drugs (NSAIDs)'.)

Physical therapy — Once the clinical diagnosis of rotator cuff tendinopathy has been made, physical therapy is the main treatment. Rehabilitation programs are based on the limited available evidence and the clinical experience of the treating clinician and therapist. For many patients, the biomechanical problems that have contributed to their rotator cuff tendinopathy are identical to the problems found in patients with shoulder impingement syndrome, and thus, the physical therapy program prescribed for each patient group is often fundamentally the same. A detailed description of such a rehabilitation program is provided separately. (See "Rehabilitation principles and practice for shoulder impingement and related problems".)

Rehabilitation protocols should be individually designed and progressive to achieve patient goals of functional pain-free motion and return to work and sport. We typically prescribe the following types of exercises.

●Mobility – Mobility exercises help to prevent shoulder stiffness and the complications of adhesive capsulitis. Generally, full shoulder range of motion should be achieved prior to strengthening exercises [6].

●Strength – Strengthening of the muscles of the rotator cuff is a basic component of physical therapy. Systematic reviews of physiotherapy interventions for shoulder pain have found that such exercises appear to be effective for short-term recovery and long-term function, but the quality of evidence is limited [63-65].

●Coordination and correction of imbalance and asymmetry – Rotator cuff rehabilitation that focuses on the restoration of proper muscle activation and appropriately balanced strength among individual muscles of the rotator cuff is important [66,67]. Exercises to strengthen the scapular stabilizers and better integrate their function with the rotator cuff are emphasized [68]. Restoration of mobility, strength, and coordination (ie, kinetic chain restoration) is an essential component of a rehabilitation program.

●Eccentric exercise – Eccentric strength exercise is the application of a load (ie, muscular contraction) during the lengthening of a muscle. Several studies suggest that eccentric exercise stimulates healing and provides effective rehabilitation of tendinopathy. Preliminary trials in rotator cuff disease suggest that this approach is beneficial, but further study is needed [67,69]. Eccentric exercise and other rehabilitation techniques using heavy loads are discussed separately. (See "Overview of the management of overuse (persistent) tendinopathy", section on 'Heavy-load resistance training'.)

●Manual therapy – Manual therapy, which may consist of joint mobilization, soft tissue massage and manipulation, and neurodynamic interventions, may decrease pain, but it is unclear whether this is associated with improved long-term function [70]. For short-term treatment, manual therapy plus exercise appears to be modestly superior to exercise alone [64]. (See "Overview of the management of overuse (persistent) tendinopathy", section on 'Joint mobilization and friction massage'.)

●Aerobic exercise – Cardiopulmonary fitness should be maintained throughout the rehabilitation process and beyond.

●Post-recovery prophylaxis ─ Once rehabilitation is complete, the need for ongoing exercises to prevent recurrence and maintain fitness should be emphasized [66]. Many sports place greater demands on the shoulder than activities of daily living. Rehabilitation and maintenance programs should incorporate exercises that simulate the specific demands of the athlete's sport.

Well-performed, controlled clinical trials of physical therapy programs for rotator cuff tendinopathy are relatively scarce [63]. A systematic review of 10 randomized trials concluded that exercise therapy improved symptoms and function in workers with rotator cuff tendinopathy and helped them to return to work [71]. Another review of 64 randomized trials assessing a broad range of physical therapy interventions (eg, exercise therapy, laser, therapeutic ultrasound, taping) for subacromial shoulder pain, including rotator cuff tendinopathy, found that exercise was as effective as surgery and better than placebo or no treatment [72].

In a large, multicenter randomized trial of patients with chronic rotator cuff conditions, no difference in the degree of improvement in symptoms or function was noted at 12-month follow-up between those treated with a home-based progressive exercise program and those treated with in-person physical therapy [73,74]. The home-based group received one session with a physical therapist, printed materials, access to instructional videos, and resistance bands, but no further in-person sessions. Clinicians considering home-based rehabilitation for a patient should note that the program used in this study began with a formal in-office physical therapy session and included quality instructional materials.

Adjunct treatments — If pain is severe when the patient first presents or no improvement is achieved within two to three months with conservative therapy, other adjunct treatment options may be added, including glucocorticoid injection and topical nitroglycerin [17].

Glucocorticoids — Although subacromial glucocorticoid injection is a common treatment for rotator cuff disorders, high-quality evidence of benefit is lacking. We believe it is reasonable to treat patients whose pain prevents them from participating in physical therapy, or whose symptoms do not improve after several weeks of conservative management including physical therapy, with a single injection of a glucocorticoid combined with an analgesic. Patients who experience significant pain when they lie on the affected shoulder at night or when they try to perform simple rehabilitation exercises with little or no resistance may benefit from such an injection. In each case, the clinician must weigh the potential benefits and risks. We do not give a glucocorticoid injection to patients if a significant rotator cuff tear is known or suspected. The general role of glucocorticoids in the treatment of chronic overuse tendinopathy is discussed separately. (See "Overview of the management of overuse (persistent) tendinopathy", section on 'Glucocorticoids' and "Management of rotator cuff tears".)

A common preparation used for subacromial injection is triamcinolone 40 mg with 1 or 2% lidocaine. (See "Intraarticular and soft tissue injections: What agent(s) to inject and how frequently?", section on 'Use of glucocorticoid injections'.)

Subacromial glucocorticoid injection appears to afford short-term pain relief from rotator cuff tendinopathy and temporary functional improvement without evidence of long-term benefit [74,75]. As nearly all such injections include a local anesthetic and are performed in conjunction with physical therapy, it is difficult to attribute benefit to the glucocorticoid alone. Local anesthetic injection alone often provides short-term symptom relief [76].

Although subacromial glucocorticoid injection is associated with an increased risk of rotator cuff tendon rupture, the attribution is not clear cut as many factors may play a role, including the type of glucocorticoid, patient age, time from injection to injury-causing stress, chronicity of tendinopathy, and status of the tendon prior to injection [77].

Nitroglycerin (glyceryl trinitrate) — Although exact mechanisms remain unclear, topical nitroglycerin may enhance collagen synthesis in damaged tendons. Topical nitroglycerin may be a useful adjunct to physical therapy for patients with persistent discomfort. In a systematic review that included four randomized trials of rotator cuff tendinopathy (10 trials total), researchers found moderate to strong evidence that topical nitroglycerin reduces pain and improves mobility, strength, and function (eg, activities of daily living) compared with placebo at short-term and 24-week follow-up [78]. (See "Overview of the management of overuse (persistent) tendinopathy", section on 'Topical nitroglycerin (glyceryl trinitrate)'.)

Unproven and experimental therapies — No high-quality evidence exists to support the use of the modalities listed here, and we do not routinely use them in the care of our patients [72,79]. Adjunct therapies may include:

●Kinesio tape – Kinesio tape has become commonplace intervention for a variety of musculoskeletal conditions, including shoulder pain. There may be a small immediate benefit in reducing pain and improving mobility when the tape is applied, but overall, there is insufficient evidence to recommend regular use [80,81]. There are no significant untoward effects from taping.

●Topical NSAIDs – Topical NSAIDs in the form of gels and patches provide some symptomatic relief in tendinopathy and osteoarthritis, and this method of drug delivery may limit systemic side effects. The use of topical NSAIDs is discussed separately. (See "Overview of the management of overuse (persistent) tendinopathy", section on 'Nonsteroidal antiinflammatory drugs (NSAIDs)'.)

●Platelet rich plasma (PRP) – PRP has been proposed as a treatment for chronic, refractory tendinopathy. However, evidence supporting its use as a treatment for rotator cuff tendinopathy is lacking. The evidence concerning the use of PRP to treat tendinopathy and other musculoskeletal conditions is reviewed in detail separately. (See "Biologic therapies for tendon and muscle injury".)

●Prolotherapy – Dextrose prolotherapy shows some promise for long-term pain control, but further studies are needed [75]. In one small study, dextrose prolotherapy provided modest reductions in pain at nine months compared with saline injection for chronic rotator cuff tendinopathy [82]. (See "Overview of the management of overuse (persistent) tendinopathy", section on 'Prolotherapy'.)

●Acupuncture – Studies of acupuncture for the treatment of tendinopathy are limited, and the technique should be considered an adjunct for pain relief while the patient performs an appropriate exercise program. (See "Overview of the management of overuse (persistent) tendinopathy", section on 'Acupuncture'.)

●Electrical stimulation, phonophoresis, and iontophoresis – Electrical stimulation, phonophoresis, and iontophoresis are three therapeutic modalities used to aid in pain relief. Phonophoresis uses ultrasound to enhance the transdermal absorption of topically applied analgesics and NSAIDs. Iontophoresis uses electrical charge for the same purpose.

●Therapeutic ultrasound – Ultrasound theoretically stimulates tendon healing via collagen production, thereby increasing tensile strength, but there is no convincing evidence of its effectiveness in tendinopathy [79]. (See "Overview of the management of overuse (persistent) tendinopathy", section on 'Ultrasound therapy'.)

●Laser – A systematic review of studies of electrotherapy interventions concluded, on the basis of low-quality evidence, that laser therapy is unlikely to add benefit beyond physical therapy in the treatment of rotator cuff tendinopathy [79]. (See "Overview of the management of overuse (persistent) tendinopathy", section on 'Laser therapy'.)

●Hyperthermia – Hyperthermia machines use a microwave power generator at 434 MHz to provide deep heating of muscles. Hyperthermia treatment is thought to increase local blood flow to damaged tissue. In a trial of 37 athletes with supraspinatus tendinopathy, those randomly assigned to treatment with hyperthermia had greater short-term reductions in pain compared with those treated with ultrasound or therapeutic exercise [83]. In a randomized trial of 92 patients, hyperthermia yielded a functional benefit equivalent to that obtained with glucocorticoid injection at 24 weeks [84]. Further research is needed to determine the effectiveness of this modality in the treatment of rotator cuff tendinopathy.

●Extracorporeal shock wave therapy (ESWT) – ESWT provides effective treatment for calcific tendinopathy of the rotator cuff. However, there is no evidence to support its use in noncalcific tendinopathy [85,86]. (See "Calcific tendinopathy of the shoulder", section on 'Extracorporeal shock wave therapy'.)

FOLLOW-UP CARE — After the initial assessment of a rotator cuff tendon injury, the patient should return to clinic within two to three weeks for re-evaluation of symptoms and function. This re-evaluation helps to determine further workup or the need for referral. Once a management plan and rehabilitation program has been established, periodic follow-up visits can be determined as appropriate. Follow-up will vary depending upon the response to treatment and the demands of the work or sport to which the patient plans to return. If a rapid return to sport or heavy labor is desired, more frequent re-evaluation (eg, monthly) may be needed.

COMPLICATIONS — Frozen shoulder (adhesive capsulitis) and rotator cuff tear are two important potential complications of rotator cuff tendinopathy. Untreated, long-standing rotator cuff tendinopathy can cause a significant loss of shoulder motion. A vicious cycle may then ensue with diminished motion leading to diminished use. Ultimately, adhesive capsulitis can result and may be difficult to treat. While few studies have been published, in one cohort study using a national health database of over 24,000 adults diagnosed with adhesive capsulitis, patients with pre-existing rotator cuff disease had six times the risk of matched controls without such conditions [87]. (See "Frozen shoulder (adhesive capsulitis)".)

Degeneration of the rotator cuff tendons in patients with chronic tendinopathy increases the risk of tendon tears. Without treatment, the initial degenerative changes cause tendon dysfunction and alterations in mechanics, leading to further degeneration and eventually tear in some patients [17]. The likelihood of these complications increases with age [31]. Published data are lacking, but tears occur with some frequency. (See "Presentation and diagnosis of rotator cuff tears".)

RETURN TO SPORT OR WORK — Once an athlete or heavy laborer demonstrates full range of motion with appropriate shoulder strength and stability, they can return to activity as tolerated [88]. A gradual, stepwise increase in activity is advisable. The nature of this stepwise return to full activity is determined by the demands of the sport or work. Shoulder rehabilitation using these principles is discussed separately. (See "Rehabilitation principles and practice for shoulder impingement and related problems".)

Coaches and athletes often ask for an anticipated time for return to play. However, given the variable nature of tendinopathy (eg, extent of tendon involvement, severity of injury) and the diverse demands among sports (eg, contact versus non-contact, thrower versus non-thrower) it is not possible to provide a standard time frame. Other factors that can affect return to play include patient age, access to quality physical therapy or athletic training resources, and athlete motivation and compliance. In addition, progression through the stages of rehabilitation may require modification based on the athlete's presentation, baseline strength and mobility, response to treatments, goals, and timing of athletic seasons. Final clearance for return to play requires that the athlete demonstrate the following:

●Sufficient shoulder strength and mobility

●Ability to perform all necessary sport-specific movements without pain using biomechanically sound technique

●Endurance and general fitness required to meet demands of the sport

Few studies are available that describe return to sport following rotator cuff tendinopathy. Most overhead athletes return to gradual training in three to four months and to full training in four to six months. It is common to abandon a competitive season, rehabilitate over six to eight months, and return to full competition the following season.

Keeping in mind the many variables that affect and may alter the timing for return to play, we estimate return to sport as follows based primarily on our experience managing athletes with moderate structural rotator cuff pathology:

●Tennis players: 10 to 12 weeks; similar for other racket sports

●Baseball pitchers: 12 to 16 weeks; nonpitchers 8 to 10 weeks

●Javelin and other track implement throwers: 8 to 10 weeks

●Weightlifters: 12 to 16 weeks

●Swimmers typically lose a season and require many months to return to full training

When working towards return to play, everyone involved in an athlete's care, including the clinician, athlete, athletic trainer or physical therapist, and coach, should be kept aware of the athlete's progress.

Return to work is also predicated upon regaining function, including full range of motion and strength in the affected shoulder. A graded return to work activity may not be possible. Therefore, the patient should perform work-specific activity without difficulty and without return of symptoms prior to resuming duties. A systematic review of clinical practice guidelines emphasized that successful return to work strategies that include shared decision-making between the patient and clinician, good communication between the patient and employer, and establishing realistic goals for returning to work [57].

SOCIETY GUIDELINE LINKS — Links to society and government-sponsored guidelines from selected countries and regions around the world are provided separately. (See "Society guideline links: General issues in muscle and tendon injury diagnosis and management" and "Society guideline links: Shoulder soft tissue injuries (including rotator cuff)".)

INFORMATION FOR PATIENTS — UpToDate offers two types of patient education materials, “The Basics” and “Beyond the Basics.” The Basics patient education pieces are written in plain language, at the 5^th to 6^th grade reading level, and they answer the four or five key questions a patient might have about a given condition. These articles are best for patients who want a general overview and who prefer short, easy-to-read materials. Beyond the Basics patient education pieces are longer, more sophisticated, and more detailed. These articles are written at the 10^th to 12^th grade reading level and are best for patients who want in-depth information and are comfortable with some medical jargon.

Here are the patient education articles that are relevant to this topic. We encourage you to print or e-mail these topics to your patients. (You can also locate patient education articles on a variety of subjects by searching on "patient info" and the keyword(s) of interest.)

●Basics topic (see "Patient education: Rotator cuff injury (The Basics)")

●Beyond the Basics topic (see "Patient education: Rotator cuff tendinitis and tear (Beyond the Basics)")

SUMMARY AND RECOMMENDATIONS

●Etiology and risk factors – Rotator cuff tendinopathy is a common cause of shoulder pain. Repetitive overhead activity in sport or work is a major risk factor. Other risk factors include rotator cuff impingement, scapular instability or dyskinesis, and older age. Knowledge of basic shoulder anatomy and biomechanics aids in diagnosis. (See 'Terminology' above and 'Epidemiology' above and "Evaluation of the adult with shoulder complaints", section on 'Anatomy and biomechanics'.)

●Differential diagnosis – Rotator cuff tendinopathy may be a manifestation of shoulder impingement but must be distinguished from other causes of shoulder and neck pain (table 2 and algorithm 1 and table 3). (See "Evaluation of the adult with shoulder complaints".)

●Presentation – Patients with rotator cuff tendinopathy complain of shoulder pain with overhead activity. Patients may localize the pain to the lateral deltoid and often describe pain at night, especially when lying on the affected shoulder. Overhead athletes often complain of pain while performing their sport, weakness, or a decline in performance. (See 'Clinical presentation' above.)

●Physical examination – Important elements of the physical examination include neck examination, rotator cuff strength testing, range of motion assessment, the painful arc test, and the Neer and Hawkins-Kennedy tests of shoulder impingement. (See 'Physical examination' above.)

●Diagnostic imaging – Many clinicians consider ultrasound to be the gold standard for the initial evaluation of rotator cuff disease. Plain radiographs are generally not indicated. (See 'Diagnostic imaging' above.)

●Treatment – Few treatments for rotator cuff tendinopathy are supported by strong scientific evidence. Initial care generally consists of cryotherapy, rest, and a short course of nonsteroidal antiinflammatory drugs (NSAIDs). We suggest that patients diagnosed with rotator cuff tendinopathy be treated with an appropriate physical therapy program rather than surgery or other interventions (Grade 2C). Physical therapy should focus on addressing deficiencies in mobility, strength, and coordination of the shoulder joint and the entire kinetic chain involved in shoulder function. Our approach to management is summarized in the following algorithm (algorithm 2).

For patients whose pain prevents them from participating in physical therapy or whose symptoms do not improve after several weeks of conservative management including physical therapy, we suggest giving a single injection of a glucocorticoid combined with an analgesic (Grade 2C). Such injection should be avoided if a significant rotator cuff tear is known or suspected. A common preparation used for subacromial injection is triamcinolone 40 mg with 1 or 2% lidocaine. Repeat injections of glucocorticoid may be harmful. The treatment of rotator cuff tear is discussed separately. (See "Management of rotator cuff tears" and "Intraarticular and soft tissue injections: What agent(s) to inject and how frequently?", section on 'Use of glucocorticoid injections'.)

Our suggested approach to the assessment and management of suspected rotator cuff injury is described in the text. A detailed discussion of a physical therapy program suitable for many patients with rotator cuff tendinopathy is provided separately. (See 'Our approach to evaluation and management' above and "Rehabilitation principles and practice for shoulder impingement and related problems".)

●Surgical referral – Orthopedic surgical referral is obtained if nonoperative therapy fails to provide relief within six to nine months or a diagnosis of a clinically significant rotator cuff tear is made. (See "Presentation and diagnosis of rotator cuff tears".)