Tendinopathy: Overview of management

INTRODUCTION — 

Tendinopathy is a clinical condition characterized by localized tendon pain with mechanical loading [1]. It commonly results from overuse and occurs in workers and athletes from recreational to elite, but may be unrelated to activity. Many patients with tendinopathy present with symptoms that have been present for a few months or longer.

The general management of chronic tendinopathy is discussed here. A diagram summarizing our approach is provided (algorithm 1). Paratendinopathy (eg, de Quervain tenosynovitis) and tendon tear represent distinct pathologies and their management is not discussed. The pathophysiology of tendinopathy, the use of biologic therapies, and the management of specific tendinopathies are reviewed separately:

●Pathophysiology of tendinopathy and biologic therapies (see "Tendinopathy: Overview of pathophysiology, epidemiology, and presentation" and "Biologic therapies for tendon and muscle injury")

●Upper extremity tendinopathies (see "Rotator cuff tendinopathy" and "Calcific tendinopathy of the shoulder" and "Biceps tendinopathy and tendon rupture" and "Elbow tendinopathy (tennis and golf elbow)" and "de Quervain tendinopathy")

●Lower extremity tendinopathies (see "Achilles tendinopathy" and "Non-Achilles ankle tendinopathy" and "Calf injuries not involving the Achilles tendon" and "Quadriceps muscle and tendon injuries" and "Running injuries of the lower extremities in adults: Risk factors and prevention")

PATIENT ASSESSMENT

History and physical examination — The history and physical examination are the most important tools for diagnosing tendinopathy. Patients with tendinopathy typically report a gradual onset of pain in the tendon most noticeable during or after tendon-loading activities. Most often, the patient has recently made substantial increases in the volume or intensity of their activity, thereby rapidly increasing the tensile or compressive loading of the tendon, or has returned to their previous exercise or activity level too quickly after a significant period of unloading (eg, holiday, illness, or another injury). Many patients also describe tendon stiffness in the morning or when starting to move after a period of rest.

The history should elucidate what type of training or activity led to the tendinopathy and clarify the level of function to which the patient aims to return. The history may also provide clues to alternative diagnoses, such as gout, fluoroquinolone toxicity, seronegative arthropathies, systemic lupus erythematosus, or tendon xanthoma.

Physical examination is most notable for focal tenderness of the involved tendon. Tendon thickening is often present but may be absent or difficult to identify in some locations, particularly close to bony insertions (eg, patellar tendinopathy, proximal hamstring tendinopathy, or lateral elbow tendinopathy). Another feature of tendinopathy is that pain with loading of the affected structure increases when higher loads or faster loading rates are used. This finding reinforces the diagnosis and provides a baseline for reassessment during treatment [2].

Paratendinopathy is a different cause of tendon pain. It refers to inflammation of the soft tissues surrounding a tendon, and involves the formation of adhesions between the tendon and tendon sheath. It is typically associated with a bout of overuse and is recognized by a history of activity-related pain associated with swelling, crepitus, and tenderness along the tendon. Diagnosis often involves clinical examination and imaging to confirm thickening of peritendinous structures and the absence of intratendinous involvement.

Assessment scores — Validated, simple functional assessment scores, such as the Victoria Institute of Sport Assessment (VISA) for patellar tendinopathy (VISA-P) or for Achilles tendinopathy (VISA-A), can help the clinician to grade symptoms and determine patient function (figure 1 and figure 2) [3-5]. The VISA-P and VISA-A questionnaires can be completed in five minutes or less and have been translated into many languages. The Patient Rated Tennis Elbow Evaluation (PRTEE) is a simple disability scale for patients with lateral elbow tendinopathy [6-8]. Such scores also provide a useful means of monitoring recovery during rehabilitation. These instruments are used for assessment and reassessment, but they are not considered diagnostic for specific tendinopathies.

Diagnostic imaging — Imaging techniques such as ultrasound, magnetic resonance imaging (MRI), and plain radiographs (for insertional tendinopathy) can be used to assess tendinopathy when clinical diagnosis is uncertain. Ultrasound is the preferred method due to its accessibility and accuracy for detecting increased tendon thickness (image 1), altered echogenicity (image 2), and vascularization (image 3), which are characteristic findings. MRI is used if ultrasound is unavailable, there are discrepancies in clinical findings making the diagnosis uncertain, or if surgery is considered. (See "Tendinopathy: Overview of pathophysiology, epidemiology, and presentation", section on 'Diagnostic imaging'.)

APPROACH TO TREATMENT — 

Tendinopathies are injuries that are slow to resolve, often requiring months for complete resolution. Patience and careful adherence to an active rehabilitation program emphasizing heavy-load exercise and a return to full activity implemented in progressive steps are the keys to successful treatment. An algorithm summarizing our approach to treatment is provided (algorithm 1). This approach is consistent with leading guidelines [9,10]. (See 'Heavy-load resistance training' below.)

Clinicians should take adequate time to explain to patients that a prolonged recovery (often three to six months, but with wide variation among patients) is likely and that they should not be discouraged by ongoing symptoms during rehabilitation. Indeed, symptoms often worsen during the initial stages of exercise therapy as loads placed on the tendon increase, but this does not mean the tendon is sustaining greater damage. Educating patients about the benefits of mechanical load in stimulating tissue repair is important to successful treatment [11].

Maintaining a realistic view of rehabilitation is essential to patient engagement and treatment success. With challenging cases, careful oversight by a physical therapist or exercise specialist is important to ensure correct, consistent performance of exercises and loads that are sufficiently heavy to promote tendon adaptation but not so heavy as to exacerbate injury, impair function, cause excessive pain, or demoralize the patient [12].

The treatment steps outlined immediately below are based upon an algorithm developed initially for Achilles tendinopathy [9,13,14]. The exact steps may vary depending upon clinical circumstance, but the principles of controlled, progressive tendon loading and gradual resumption of activity remain central to any program. Time frames are approximate.

●Initial assessment – Clinicians first assess the patient with tendon pain as follows: Evaluate structures and joints that function in concert with the involved tendon (ie, kinetic chain); examine peritendinous structures; rule out complete or partial tendon rupture; rule out alternative diagnoses. (See 'Patient assessment' above.)

●Activity modification, exercise program, and reassessment – If tendinopathy is the leading diagnosis, reduce or modify activities that provoke tendon pain and, guided by symptoms (using the pain-monitoring model [15]), begin a controlled exercise program using progressively heavier loads under appropriate supervision for 12 weeks at a minimum [16]. Some clinicians perform a reassessment at six weeks, particularly if the patient is not under the care of a physical therapist, to ensure compliance and appropriate loads. (See 'Activity modification and tendon load' below and 'Heavy-load resistance training' below.)

If symptoms increase during exercise therapy, clinicians should do the following:

•Modify the exercise program as needed. This may include adjusting the weight or resistance used for particular exercises, changing the exercises performed, limiting the range of motion used for particular exercises, adjusting the number of sets and repetitions for particular exercises, or changing the frequency of rehabilitation sessions.

•Reassess the kinetic chain looking for other pathology or mechanical flaws. (See 'Biomechanical modification' below.)

•Reassess other provocative activities, including technique, volume, and intensity, making modifications as indicated. Such activities may include those of daily living, running, and jumping.

With insertional tendinopathy, better initial results are achieved when patients avoid bony compression of the affected tendon at the end-range of joint motion [17,18].

●Continue program if improvement – If the patient improves, continue the exercise program for 3 to 12 months and gradually introduce higher tendon-loading activities in line with the physical demands of the patient's ultimate activity goals. For a given sport, such activities may include running, rapid changing of direction (ie, cutting), jumping, or throwing, depending on the tendinopathy location.

●Reassess if no improvement – If there is no improvement after 6 to 12 weeks following modification of the exercise program, reassess the diagnosis and evaluate for the possible contribution of systemic comorbidities, altered biomechanics, psychosocial factors, and loading parameters. If the diagnosis is confirmed, modify the exercise program (addressing parameters described above) and consider adding adjunct therapies. These may include supportive treatments, such as joint or tissue mobilization and orthoses, or secondary interventions, such as extracorporeal shock wave therapy. (See 'Supportive interventions' below and 'Secondary treatments' below.)

If the tendinopathy diagnosis and comorbidity status are confirmed and there is still no improvement after an additional 6 to 12 weeks, continue the exercise program and consider other secondary treatments. Depending upon patient preference, clinician experience, and available resources, investigational treatments may be tried, or the clinician may opt for rheumatologic or surgical referral as appropriate. (See 'Investigational treatments' below and 'Indications for surgery' below.)

Investigators have identified subgroups among patients with tendinopathy that may warrant modification of standard treatment approaches to accommodate biopsychosocial and physiologic factors. As an example, outcomes using standard exercise approaches may be inferior in sedentary or obese patients [19-21], and psychologic factors such as catastrophization and fear of movement (kinesiophobia) may affect some patients [22]. Education using pain science principles may enhance rehabilitation outcomes for this subgroup of patients [23-26].

Chronic pain may become dysfunctional. Modifiable factors such as fear of movement and misconceptions about the association between pain and tissue damage can contribute to such dysfunction [27]. Encouraging tendon-loading activities despite pain can help to reshape patients' perceptions. Alongside physical factors, the psychosocial aspects of long-term pain are increasingly recognized as critical in managing tendinopathy [28].

TREATMENTS

Range and limits of available treatments — A variety of approaches have been advocated for the treatment of tendinopathy. The most common and well-supported strategies are presented immediately below (see 'Primary treatments' below). Less well-established and investigational approaches are discussed below (see 'Secondary treatments' below and 'Investigational treatments' below). An algorithm summarizing our approach to treatment is provided (algorithm 1).

The medical literature describes several differences among tendon types and specific tendons such that caution is warranted before generalizing treatment effects across different tendinopathy locations. Reported differences include sensitization of the central nervous system in upper limb but less with lower limb tendinopathies [29,30], variable function in energy storage and postural control [31], and unique anatomic and biomechanical features of specific tendons. Such differences may explain in part why clinical studies seldom identify a universal effect for a given intervention across all tendinopathies.

Primary treatments — The success of conservative treatment using the primary treatments discussed here frequently depends upon a coordinated program of education, reduction of aggravating activities and replacement with tolerable activities, modification of potentially contributing underlying biomechanical factors, and tendon-specific exercise therapy, with a gradual increase in tendon loading.

Activity modification and tendon load — Patients with tendinopathy should modify their usual activities to reduce the loads placed on the injured tendon. Activity modification requires limiting both the volume and intensity of tendon loads for a designated period to allow for symptoms to resolve. The duration of the activity modification depends on changes in symptoms and the response to exercise therapy, which vary widely among individuals. The pain-monitoring model provides a useful method for ensuring appropriate loads [15]. This method uses patient ratings of pain and stiffness to guide activity.

While evidence suggests higher pain thresholds may be used, in clinical practice, many physicians and physical therapists do not permit patients to exceed pain levels of 2 or 3 on a 0-to-10 scale. Keeping pain within acceptable levels may improve patient compliance with exercise therapy and allow them to continue with some recreational activity. As an example, a runner with Achilles tendinopathy may be permitted to do some limited running provided their pain during and after activity does not exceed a level of 3. (See 'Heavy-load resistance training' below.)

According to a randomized trial of 38 patients with Achilles tendinopathy, greater pain during exercise may be tolerable, even up to 5 on a 0-to-10 scale, without adversely affecting outcomes [15]. However, for many patients, a more conservative approach such as that described above may be prudent.

For patients who engage in activities that place high loads on tendons (eg, sports involving sprinting and jumping) or that involve prolonged lower-intensity loads, particularly on tendons of the upper extremities, it is important that coaches and employers be aware of activity modifications in the treatment plan.

In the athletic setting, training (ie, loading) errors are an important contributor to the development of tendinopathy [32]. Rapid increases in training volume, intensity, and/or frequency are well-recognized causative factors, while others (eg, a low level of tendon-loading capacity) may also play a role [33,34]. Establishing a moderate-to-high chronic training load is protective against tendon injury, while chronic underloading is thought to increase susceptibility [33,34]. The onset of tendinopathy frequently occurs during rapid reloading after a period of deloading (eg, return to intense training following a holiday, illness, or another injury). Consistently maintaining moderate, repetitive loads is necessary for tendons to retain resilience.

Rehabilitation seeks to rebuild tolerance for higher volumes of tendon loading through a graduated progression of resistance training [35]. Depending on patient activities and aspirations, the ultimate goal is to tolerate high rates of loading, as occur during sprinting, jumping, or throwing. The key to successful rehabilitation of tendinopathy appears to be determining the optimal load for exercises as well as the desired rate of progression of the load. (See 'Heavy-load resistance training' below.)

Biomechanical modification — Whenever possible, the biomechanics of major tasks possibly contributing to the tendinopathy should be analyzed and optimized by an ergonomics specialist, a trained physical therapist or kinesiologist, a knowledgeable sports medicine clinician, or a comparable expert. This approach has not been studied in large, randomized trials but is supported by clinical experience and biomechanical modeling.

Studies have found mixed associations between abnormal biomechanics or specific performance characteristics and the development or progression of tendinopathy [36-40]. As an example, computer users in one study were randomly assigned to use four different keyboard types [41]. A reduction in tendinopathy symptoms occurred after several months in patients using an ergonomic keyboard. In another small, prospective cohort study of auto workers, elbow tendinopathy was strongly associated with the time spent with the wrist out of neutral position during work [40]. A systematic review of prospective and cross-sectional studies concluded that specific biomechanical factors (eg, increased eversion range of motion of the rearfoot or increased duration of the gait cycle spent in rearfoot eversion) during running may predispose to Achilles tendinopathy, and that biomechanical assessment of running may be helpful in making treatment decisions for those with an overuse tendinopathy stemming from running [42,43]. As another example, cohort studies have found that limited ankle dorsiflexion is associated with patellar tendinopathy in athletes participating in jumping sports (eg, volleyball, basketball) [44-46]. (See "Clinical assessment of walking and running gait".)

Heavy-load resistance training

Principles and approach — Controlled, progressive resistance training using relatively heavy loads should serve as the cornerstone of treatment for most cases of chronic tendinopathy, including Achilles, patellar, and lateral elbow tendinopathy [47]. This approach is supported by the results of nearly all studies of tendinopathy management where a well-designed resistance exercise program was considered the primary intervention [47-51]. Exercise programs with higher intensities (ie, using higher tendon loads) and lower frequencies (ie, using resting days between training sessions) tend to be more effective, likely because they involve stronger stimuli and allow for sufficient recovery [47].

Specific instructions for implementing a resistance exercise program for the treatment of tendinopathy are beyond the scope of this review, but programs using a phased approach, starting with early pain control and progressing to controlled exercises (eg, isometric and isotonic loading) and then to more demanding functional exercises, are supported by the literature [52,53]. Modifications in exercise protocols and loads are needed for upper extremity tendons and weightbearing lower extremity tendons. Our fundamental approach to the management of tendinopathy is described above. (See 'Approach to treatment' above.)

Rehabilitative exercise programs for the management of specific tendinopathies are found in multiple UpToDate topics, including those listed here:

●Achilles tendinopathy (see "Achilles tendinopathy")

●Patellar tendinopathy (see "Patellar tendinopathy")

●Elbow tendinopathy (see "Elbow tendinopathy (tennis and golf elbow)")

●Rotator cuff tendinopathy (see "Rehabilitation principles and practice for shoulder impingement and related problems")

The resistance exercises used for rehabilitation include different types that may be implemented in different ways [9,14,54]:

●Isometric exercise involves the maintenance of tension within a muscle held in a static position (neither lengthening nor shortening)

●Isotonic exercise involves a muscle changing in length (shortening or lengthening or both), resulting in movement of one or more joints, while working against a constant resistance (eg, fixed weight)

●Eccentric exercise involves the application of a load to a lengthening muscle

●Concentric exercise involves the application of a load to a shortening muscle

●Plyometric exercise involves rapid, explosive movements, like jumping or bounding, designed to harness the elastic function of muscles and tendons

No specific exercise type has demonstrated greater effectiveness with a clinically relevant effect size. Programs of greater intensity (ie, higher load) and lower frequency (allowing adequate recovery) appear to be more effective [47].

Exercises incorporating concentric and eccentric phases can be done bilaterally with high loads [55,56]. Plyometric exercises, particularly those that mimic the functional demands of the tendon during the patient's sport or occupation, are important progressions used during the later stages of rehabilitation to ensure full recovery of the tendon sufficient to meet activity demands.

The strain from exercising with progressively heavier tensile loads, moved in a slow, controlled manner, stimulates tissue remodeling. This process is termed mechanotransduction [11]. Such exercise may be uncomfortable initially, but if performed properly, it should not cause severe pain acutely or result in any subsequent worsening of symptoms (eg, more severe pain or joint swelling 24 hours after the exercise).

During exercise therapy, discomfort should be kept within moderate levels that do not reflect further injury [57]. The type and amount of loading prescribed should be tailored to the patient, taking into consideration their injury, pain and fatigability, and the level of function ultimately required (based on vocational or sporting demands and patient-specific goals). Progression (ie, increases in load or volume) should be done gradually and carefully monitored. Early during rehabilitation, exercises may be performed once or twice daily, but as strength improves and the load is increased, exercise frequency is reduced (eg, every other day) to facilitate necessary recovery.

Regardless of the tendon involved, it is often helpful to have a knowledgeable therapist supervise the patient beginning a rehabilitation regimen involving heavy-load resistance exercise [58]. Such supervision may be especially useful for the rehabilitation of lower limb tendinopathy, as the loads used frequently reach multiples of body weight during athletic activity or heavy labor. However, once patients demonstrate competence with the exercises, they can continue treatment at home. Home-based rehabilitation may be appropriate from the outset for patients experienced in exercise therapy, and for patients without ready access to physical therapy because of distance or insurance, it may be the only option.

The therapist must ensure that exercise technique is biomechanically sound, and the intensity and frequency of the program are appropriate to the patient and clinical circumstance [59]. As an example, for rotator cuff tendinopathy, an exercise program that addresses not only the injured muscle-tendon unit (eg, supraspinatus) but also the coordination and function of the scapulothoracic and scapulohumeral joints should be prescribed [60]. In addition, the therapist should be able to supervise a graduated transition from the heavy, slow muscle-tendon loading program emphasized early during rehabilitation to the higher rate (ie, velocity) of loading required later during rehabilitation as an athlete prepares for return to full sport. If this progression is too rapid, symptoms frequently recur. Elite and ambitious recreational athletes may need closer supervision to prevent them from approaching their rehabilitation too aggressively.

Evidence — Evidence supporting heavy-load exercise therapy is evolving for both lower and upper extremity tendinopathies. Several early randomized trials and observational studies in patients with midportion Achilles tendinopathy found unilateral, eccentric exercise to be effective treatment [57,61-66]. Subsequent studies suggest that bilateral exercise involving isotonic (both eccentric and concentric) movements performed in a similar fashion (ie, controlled movement using heavy loads) may be equally effective [48,55,56,67,68]. Two meta-analyses were unable to determine the superiority of one exercise type over another for Achilles tendinopathy [49,69] or in both Achilles and patellar tendinopathy [68].

Isometric exercise was previously thought to provide an analgesic effect for tendinopathy [70]. However, the results of a systematic review of 10 studies, most of limited quality, suggest that isometric exercises are not superior to isotonic exercise for managing chronic tendinopathy, with responses varying both within and across tendinopathy populations, and unlikely to provide an analgesic response for many patients [71]. Nevertheless, isometric exercise may benefit some patients and thus may still be included in an exercise therapy program.

In a randomized trial of 76 patients with confirmed, chronic patellar tendinopathy, treatment that included plyometric exercises following earlier therapy with isotonic exercise resulted in greater improvement among athletes [52]. Energy-storage exercises such as plyometrics may be a useful progression to implement before beginning sport-specific exercises.

Studies of treatment for tendinopathy of the upper limb report similar results for an exercise-based approach. A systematic review of eight studies of lateral elbow tendinopathy found statistically significant short-term improvements in pain and function with eccentric strengthening exercises, although long-term results were inconclusive [51]. A systematic review of 10 low to moderate quality studies found that patients with rotator cuff tendinopathy managed with exercise therapy reported greater functional improvement than those receiving placebo or no treatment [72].

Supportive interventions

Anti-inflammatory medications — The majority of tendinopathies demonstrate minimal or no cellular inflammation [73]. However, in some cases there may be a low level of biochemical inflammation that contributes to pain, which may be a reasonable target for treatment [74]. Overall, anti-inflammatory medications do not appear to provide long-lasting effects.

Clinical studies of anti-inflammatory medications report conflicting results for short- and long-term pain reduction in patients with tendinopathy [75-80]. Glucocorticoid injections are effective for short-term pain relief but may lead to poorer long-term outcomes [81]. (See 'Nonsteroidal anti-inflammatory drugs (NSAIDs)' below and 'Glucocorticoids' below.)

Nonsteroidal anti-inflammatory drugs (NSAIDs) — Oral NSAIDs (and acetaminophen) may be helpful for short-term (eg, five to seven days) pain relief. In addition, NSAIDs may reduce tenocyte motility and activity [82], which may be useful during the early phases of tendinopathy. However, given the absence of prominent inflammation in most cases of tendinopathy, conflicting evidence for efficacy in clinical trials [75-80], and the known systemic side effects associated with chronic use, we prefer to avoid long-term NSAID use. (See "Nonselective NSAIDs: Overview of adverse effects".)

Few studies have investigated NSAIDs in this setting. In a randomized trial of 69 patients with Achilles tendinopathy (<3 months duration) undergoing the same 12-week physical rehabilitation program, no difference in functional outcome or diagnostic imaging at one week, three months, or one year was noted among those given naproxen for seven days compared with those given placebo early in their course [75]. In an open-label randomized trial of 33 patients with rotator cuff tendinopathy, those treated with ibuprofen over a six-week period had greater improvements in function and pain than those treated with acetaminophen [83].

Multiple controlled trials support the effectiveness of topical NSAID gel or iontophoresis for short-term pain control [84-88]. Topical NSAIDs may cause fewer systemic side effects than oral NSAIDs and systematic reviews have found no difference in long-term treatment outcomes [87,89]. Should patients require ongoing treatment with high doses of analgesics despite optimal conservative management, the clinician should consider alternative diagnoses, such as inflammatory arthropathy.

Glucocorticoids — The effectiveness and risks associated with glucocorticoid treatment of tendinopathy appear to vary with the condition, duration of symptoms, and mode of drug delivery (eg, local injection versus systemic treatment). As a long-term treatment for tendinopathy-related symptoms, glucocorticoids are potentially harmful, and we suggest they be avoided [90]. In select cases, local glucocorticoid injection may be useful for the short-term treatment of symptoms, namely pain, thereby enabling patients to participate more actively in physical therapy. When considering glucocorticoid injection for lateral elbow, rotator cuff, Achilles, and other tendinopathies, clinicians must balance the benefit of short-term pain reduction with the increased risk of worse long-term outcomes, including tendon rupture, although this risk appears to be low [56,81,91].

As an example of differing approaches, some clinicians use glucocorticoid injection for rotator cuff tendinopathy to facilitate rehabilitation. Conversely, other clinicians avoid glucocorticoid injections in pure tendinopathies affecting the lower extremities (eg, patellar, peroneal) to avoid tendon injury. The use of local glucocorticoid injection for short-term symptomatic relief is discussed in UpToDate topics devoted to specific tendinopathies.

Glucocorticoids inhibit tendon adaptations to load [92] and collagen synthesis, possibly increasing the risk of tendon rupture, more so in the lower limb [93]. In patients with chronic symptoms of patellar or Achilles tendinopathy, glucocorticoid injections have not been shown to provide added benefit to patients treated with exercise therapy [56,94]. A systematic review concluded that subacromial injections are effective at reducing symptoms, but the patients included suffered from a variety of pathologies (eg, adhesive capsulitis, labral injuries) so it is difficult to draw meaningful conclusions [95]. According to another systematic review, glucocorticoid injections for lateral elbow tendinopathy reduce pain initially but ultimately increase recurrence rates and lead to inferior long-term outcomes [89,96]. Subsequent systematic reviews of randomized trials involving glucocorticoid injections for patients with lateral epicondyle tendinopathy or tendinopathy of the rotator cuff or Achilles tendon have reported similar findings [81,97].

Judicious use of local glucocorticoid injection to reduce pain and improve function in the short term can be a reasonable part of a comprehensive treatment plan. Multiple trials report reductions in acute pain from local glucocorticoid injection [81,90,95,98]. Glucocorticoids may also be administered via iontophoresis. As examples, in a small randomized trial, glucocorticoids delivered by iontophoresis improved pain and stiffness in patients with Achilles tendinopathy of less than three months duration [99], while a similar trial found that iontophoresis with glucocorticoid and lidocaine improved pain and function in patients with lateral elbow tendinopathy [100]. (See "Elbow tendinopathy (tennis and golf elbow)", section on 'Secondary management' and "Rotator cuff tendinopathy".)

Joint mobilization and friction massage — Although there is little evidence to support their use across the board, certain manual techniques specific to an anatomic location may serve as a useful adjunct to active rehabilitation. Clinical experience suggests that joint or muscle dysfunction may contribute to altered muscle activation and movement patterns, and abnormal tendon loading. This dysfunction may be amenable to treatment with manual therapy techniques performed by an appropriately trained therapist.

In one randomized trial, patients with chronic lateral elbow tendinopathy were randomly assigned to receive physiotherapy including joint mobilization, corticosteroid injections, or a wait-and-see approach [101]. Patients in the physiotherapy group recovered more quickly than those in the wait-and-see group and had significantly better long-term outcomes than the corticosteroid group. Several case studies also support joint mobilization for other upper extremity tendinopathies [102].

Historically, friction massage applied directly to the painful tendon (the Cyriax approach) was considered an important treatment for tendinopathy [103]. Animal studies demonstrate that friction massage can increase tendon fibroblast activity [104]. However, a systematic review concluded that friction massage combined with other physiotherapy modalities (not including therapeutic exercise) does not consistently improve pain, grip strength, or functional status in tendinopathy patients [105]. This aligns with our clinical experience and subsequent clinical trials, which show minimal benefit from friction massage compared with exercise therapy [106,107].

Stretching

For treatment — Stretching may be used for symptomatic relief of muscle spasm and for lengthening functionally shortened muscle-tendon units. In addition, targeted stretching may improve kinetic chain function. For this reason, stretching of muscles not directly connected to the affected tendon may be included in physical therapy. As an example, stretching of the calf muscles may be helpful for patients with patellar tendinopathy and restricted ankle dorsiflexion [52].

Of note, stretching of insertional tendinopathy (eg, Achilles or proximal hamstring) may exacerbate the condition due to entheseal compression. If present, partial tendon tears may also be exacerbated by stretching.

Despite the absence of definitive studies, many sports clinicians and physical therapists routinely include stretching in their programs for the prevention and treatment of tendinopathies. If stretching is prescribed, we suggest the following guidelines:

●Stretch when muscles are warm – Perform stretching exercises following activity, when muscles are warm; stretching before activity does not prevent injury and may cause transient decreases in strength [108,109]. Before activity, perform a gradual active warm-up that involves the major muscles to be used. Stretching of warm muscles induces greater gains in flexibility than stretching without warming [110].

●Stretch regularly (three to five days per week) – Flexibility gains from a single stretching session last 90 minutes, but gains from regular regimens persist for weeks after cessation [111].

Alternatives to static stretching, such as proprioceptive neuromuscular facilitation (which incorporates brief periods of muscular contraction preceding passive stretching) and dynamic stretching (which involves active movements of a joint to lengthen muscles), may be beneficial, but studies are limited and further research is needed. Supervised forms of yoga or similar approaches, performed over months or years, may improve general or specific flexibility in a more strategic and controlled manner. Hatha yoga has been reported to produce improvements in mobility and fitness equivalent to stretching and calisthenics. (See "Overview of yoga".)

For prevention — While stretching has long been advocated for preventing tendinopathy, evidence is lacking. A systematic review found insufficient evidence to support or refute the use of stretching to treat or prevent Achilles tendinopathy [112]. Another systematic review found no clear evidence that stretching prevents sports-related injury [108].

Ice or heat — Neither ice nor heat are important treatments after the acute phase of injury but may serve as useful adjuncts for reducing symptoms in some patients during ongoing treatment of chronic tendinopathy. Controversy surrounding the use of ice or heat to treat chronic tendinopathy stems from historical debates about the role of inflammation in the condition. One small study found that ice provided no benefit when added to a program of eccentric exercise to treat lateral elbow tendinopathy [113]. Conversely, one small randomized trial found that heat (delivered by microwave diathermy) improved patient satisfaction with treatment [114].

Orthoses — Orthoses are customized or prefabricated devices designed to support, align, or correct musculoskeletal function and are commonly used to manage lower-limb conditions. For tendinopathies, orthoses can help to alleviate pain and aid healing by reducing the loads placed on affected tendons during activity. This may be accomplished by providing cushioning, redistributing pressure, and correcting biomechanical problems. Examples include insoles for Achilles tendinopathy, a patellar strap for patellar tendinopathy, and a counterforce brace for lateral elbow tendinopathy. Details pertaining to the use and effectiveness of orthoses can be found in topics devoted to specific tendinopathies.

Secondary treatments

Topical nitroglycerin (glyceryl trinitrate) — Given its low cost, relative safety, and limited evidence of benefit for a condition that is not easy to treat, topical nitroglycerin (TNG) may be a reasonable adjunct treatment for patients being managed with physical therapy or if other conservative measures have failed. TNG should be used in conjunction with an active rehabilitation regime emphasizing heavy resistance exercise, and patients should be advised that it may take three to six months to experience significant improvement. (See 'Heavy-load resistance training' above.)

Nitroglycerin (also referred to as glyceryl trinitrate) patches are placed directly over affected tendons to deliver nitric oxide, a potent signaling molecule that stimulates collagen synthesis in tendon cells, among its many effects. The dose used in most trials has been either one-fourth or one-half of a 5 mg/24-hour or 10 mg/24-hour patch, left in place continuously for a designated period.

When using TNG, the skin should be monitored for signs of irritation, and the patient should be made aware that lightheadedness ("dizziness") and headaches are potential side effects. Contraindications include patients with hypotension, migraine headaches, rosacea, head injury, severe anemia, and those taking any other source of nitrates (eg, nitroglycerin, phosphodiesterase inhibitors such as sildenafil). Overall, nitric oxide therapy is safe; the dropout rate averages approximately 18 percent (generally headache and skin rash) [115].

Evidence supporting the use of TNG remains limited. A 2019 systematic review and meta-analysis [115] identified 10 randomized controlled trials of TNG of variable quality, of which two were not placebo controlled [116,117], and found that treated patients were more likely to become asymptomatic during activities of daily living. The authors concluded that "randomized controlled trials in all tendinopathies reveal improved midterm (up to six months) improvements in pain, strength, and patient satisfaction." Pain at rest was unaffected. Individual studies have reported limitations to clinical benefit. As an example, in the only controlled trial of TNG for patellar tendinopathy, 33 patients were randomly assigned to TNG or placebo, and no differences between groups were found in pain reduction, condition severity, or patient satisfaction over 24 weeks [118]. A larger trial in patients with Achilles tendinopathy treated with an eccentric exercise program reported no added benefit from TNG compared with placebo [119].

Extracorporeal shock wave therapy — The use of extracorporeal shock wave therapy (ESWT) as an adjunct for treating chronic soft tissue injury is evolving, although study results continue to be mixed [120]. We concur with existing guidelines that it is reasonable to use ESWT in cases of chronic tendinopathy that are not improving adequately with a high-load resistance exercise program [9,10]. When determining whether to use ESWT, clinicians should consider patient preferences, costs, risk of adverse events (significant complications are uncommon), uncertainty of effectiveness, availability, and local expertise.

Many trials of ESWT have been limited by inconsistent treatment protocols, small sample sizes, and other methodologic issues. Future controlled trials of ESWT should focus on specific tendon injuries, use newer equipment and methods, and apply consistent protocols for shock wave administration to assess whether this treatment improves patient-important clinical outcomes.

A number of early clinical trials examined the efficacy of ESWT in tendinopathy and found marginal improvements over placebo [121-124]. These trials involved a range of treatment protocols. Subsequent systematic reviews have reached mixed conclusions about the effectiveness of ESWT for treating tendinopathy. Two reviews concluded that there is insufficient evidence to recommend ESWT for lateral elbow tendinopathy or noncalcific rotator cuff tendinopathy [89,125], while a 2011 review concluded there was insufficient evidence to recommend ESWT for the treatment of midportion Achilles tendinopathy [126]. In addition, a few small, limited, randomized trials investigating the combination of exercise therapy and ESWT in the treatment of rotator cuff and patellar tendinopathy have found no added benefit from ESWT [127-129].

Other trials have reported positive results. A meta-analysis limited to randomized trials (n = 29) assessed the use of ESWT for lower limb tendinopathies and at immediate follow-up reported a pooled reduction in pain (standardized mean difference -1.41; 95% CI -2.01 to -0.82) and improvement in function (standardized mean difference 2.59; 95% CI 1.54-3.64) [130]. Improvement persisted at 3 and 6 months and beyond 12 months. The meta-analysis found that focused, high-dose ESWT was more effective than radial, high-dose ESWT. Another meta-analysis of moderate-quality evidence found that radial ESWT was more effective than conservative treatment in the management of proximal hamstring tendinopathy [131].

Investigational treatments — Multiple therapies for chronic tendinopathy, even some that are commonly used, often lack supporting evidence. Network meta-analyses of studies of multiple tendinopathies (Achilles, gluteal, patellar, and lateral elbow) report no clinically relevant differences among such treatments [132-134].

When considering adjunct treatments, the clinician should evaluate their safety, and consider the evidence of their effectiveness, time required, costs to the patient, and availability. This information should be discussed with the patient in the context of their goals and preferences. Possible adjunct therapies include those discussed below.

Prolotherapy — Prolotherapy involves injecting a substance, usually dextrose and lidocaine, either into the tendon or at the enthesis, with the intent of stimulating a repair response. Study results are mixed, and well-performed randomized trials are needed to assess this treatment before it can be recommended. Prolotherapy is associated with few side effects [135].

A meta-analysis of 18 heterogeneous trials found that prolotherapy was better than other injectables for long-term (>6 months) relief of pain and improvement in function for rotator cuff tendinopathy [98]. However, overall, small randomized trials performed in patients with a range of tendinopathies report mixed results [136-140].

Sclerotherapy — Chronic tendinopathy is associated with an angiofibroblastic response (ie, new blood vessel formation, also referred to as "neovascularization" – coupled with fibrosis). Injections of a sclerosing substance (eg, polidocanol) to reduce neovascularity have shown promise in early small clinical trials for chronic midportion Achilles and patellar tendinopathy [141,142]. However, studies are limited, and larger, well-performed trials are needed to determine the effectiveness of sclerotherapy [135,143]. The technique appears safe as very few adverse events have been reported.

Injections target abnormal peritendinous blood vessels using ultrasound guidance. Pilot studies have demonstrated the feasibility of this technique for patients with de Quervain's tenosynovitis, flexor carpi ulnaris tendinopathy, supraspinatus tendinopathy, and midportion Achilles tendinopathy [137,144-146]. A retrospective observational study of 113 Achilles tendinopathy patients failed to confirm the initial reports of clinical benefit with polidocanol treatment [147]. One small randomized trial compared polidocanol injections with placebo for treating chronic Achilles tendinopathy and found no significant difference in pain reduction or functional outcomes between groups at three and six months [148].

Autologous blood and platelet-rich plasma injection — The injection of autologous blood or platelet-rich plasma (PRP), often under ultrasound guidance, is performed with the intention of stimulating a healing response in patients with chronic tendinopathy. High-quality evidence of the efficacy of these treatments is sparse, and well-designed, controlled trials frequently do not show superiority over placebo [149-152]. The use of biologic therapies such as PRP for the treatment of tendon and muscle conditions is reviewed in detail separately. (See "Biologic therapies for tendon and muscle injury".)

Dry needling — Needling, with or without injection of other substances, has generally been investigated in patients with tendinopathy that has not responded to conservative management. A narrative review of studies of dry needling for the treatment of tendinopathy considered three systematic reviews, seven randomized trials, and six cohort studies of both upper and lower limb tendinopathies [153]. Most studies reported statistically significant improvements in patient symptoms and the authors concluded that available, albeit limited, evidence suggests that dry needling is safe, inexpensive, and effective treatment for tendinopathy. A subsequent systematic review found that available evidence was of low quality and accurate estimates of effect could not be provided [154]. Heterogeneity in treatment protocols, including needling frequency, use of ultrasound guidance, and use of other therapies, limit the generalizability of these findings. Dry needling requires training and experience to perform properly, and results may vary in part depending on clinician skill.

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 that stimulates tendon repair. The use of acupuncture for analgesia is discussed separately. (See "Overview of the clinical uses of acupuncture".)

A systematic review of four small, limited, randomized trials found acupuncture to be of short-term benefit for reducing acute pain in patients with lateral elbow tendinopathy, but there was insufficient evidence to support or refute its effect upon long-term outcomes [155]. Two small randomized trials reported positive results in the treatment of Achilles tendinopathy [156,157].

Ultrasound therapy — Ultrasound therapy has been available for several decades, but definitive evidence supporting its efficacy in treating tendinopathy is lacking. A systematic review of 13 randomized trials involving patellar tendinopathy patients concluded, based upon limited evidence, that ultrasound can likely be excluded as a treatment due to marginal efficacy [158]. Another systematic review of randomized trials of physical interventions for lateral elbow tendinopathy found insufficient evidence to support or refute the effectiveness of ultrasound as a lone treatment [89]. A single randomized trial comparing hyperthermia treatment to continuous ultrasound therapy in patients with either Achilles or patellar tendinopathy concluded that ultrasound treatment was inferior [114]. A systematic review of three trials of interventions for rotator cuff tendinopathy found therapeutic ultrasound to be inferior to laser therapy and of no greater benefit than placebo [72].

Laser therapy — Low-level laser therapy (LLLT; also known as "cold laser") has been available for many years, but convincing evidence of its clinical efficacy is lacking. Despite the development of LLLT dosing guidelines for the treatment of tendinopathies by the World Association of Laser Therapy (WALT), a systematic review of controlled clinical trials reported inconsistent results with 12 studies showing some benefit while 13 reported inconclusive results or no effect [159]. Studies varied in quality and in the laser doses used.

A 2005 systematic review of studies of LLLT for patients with lateral elbow tendinopathy concluded that there was no clinically relevant effect, either in the short or long term, compared with placebo [89]. Several controlled trials in which patients were randomly assigned to treatment with LLLT or placebo laser reported that active laser treatment did not improve outcomes beyond those achieved with eccentric exercise [160,161]. Another randomized trial reported no effect of LLLT (using WALT guidelines) as an adjunct to eccentric exercise [162]. However, some trials have reported significant symptom improvement in patients treated with active laser versus placebo [163,164].

Blood flow restriction — Blood flow restriction (BFR) has been used by bodybuilders to stimulate muscle hypertrophy and in patients with osteoarthritis or after joint surgery as a means of strengthening muscle-tendon units with lower absolute loads. Several studies describe similar applications for tendinopathy [165,166]. In a randomized trial of 46 patients with lateral elbow tendinopathy, low load resistance using genuine BFR produced greater improvements in pain, strength, and function than the same resistance exercises performed using sham BFR [167]. Further research is needed to verify these findings and determine optimal parameters for treatment before BFR can be widely recommended.

INDICATIONS FOR SURGERY — 

The treatment of chronic tendinopathies involves rehabilitation combined with conservative medical management. Surgical consultation is reasonable if there is no improvement after 6 to 12 months of diligent physical therapy using a well-designed program in combination with adjunct medical treatments and after other conditions have been excluded or managed [9,168]. (See 'Approach to treatment' above and 'Treatments' above.)

A variety of surgical treatments have been advocated, depending upon the location of the tendinopathy and surgeon preference. Referring clinicians should carefully assess the risks and benefits of surgery. A systematic review concluded that the degree of success claimed in surgical studies of tendinopathy repair correlates inversely with the quality of the study [169,170].

Open surgical procedures for treatment of tendinopathy involve incising the paratenon and removing adhesions, followed by debridement of macroscopically degenerative tissue, or in the case of the shoulder, patella, or Achilles, calcific deposits [171]. Sometimes longitudinal incisions are made in the tendon with the intention of promoting a repair response [172]. A similar strategy of longitudinal incision and debridement may be achieved endoscopically [173-175].

Resection or drilling of the tendon's attachment points have also been described [171,176]. This procedure entails a prolonged recovery (approximately 6 to 12 weeks of immobilization) due to the time needed for tendon and bone healing. Overall recovery may require 9 to 12 months.

Minimally invasive surgical procedures have been developed. The advantage of such procedures is that the tendon itself is not disturbed, and thereby, lengthy rehabilitation may be avoided. For the patellar tendon, an endoscopic procedure involves debriding the area of neovascularization on the posterior surface of the tendon until flow in the neovessels is no longer observed [177]. For midportion Achilles tendinopathy, a similar approach involves stripping or debriding the neovascular area on the anterior surface of the tendon. This procedure may include resection of the associated pathologic plantaris tendon or bursae, if indicated [178]. (See "Achilles tendinopathy".)

Among the minimally invasive techniques is percutaneous ultrasonic tenotomy (eg, Tenex), which uses a needle to apply high-intensity ultrasound waves to debride tissue, with concurrent tissue lavage. The technique has been used for lateral elbow [179,180], gluteal [181], and other tendinopathies. Further research is required to determine the effectiveness of this approach [182].

Studies comparing surgery to rehabilitation programs (such as those described above) in the treatment of tendinopathy report equivalent long-term results for function, pain, and overall quality-of-life measures. In a systematic review of 12 randomized trials (two rated good quality and four moderate quality), surgery was found to yield superior results when compared with no treatment or placebo but equivalent results compared with sham surgery and exercise therapy [168]. The authors recommend conservative exercise-based interventions for 12 months before surgery is considered. However, caution should be exercised when interpreting the direct comparisons included in these disparate studies, as in many cases surgery was an intervention of last resort, and patient cohorts were not equivalent.

Should surgery be needed, limited evidence suggests that endoscopic procedures yield modestly better results in patient satisfaction and allow for a more rapid return to sport and full activity than open procedures [183,184]. Minimally invasive and arthroscopic procedures have lower complication rates [185]. A large systematic review of studies of the surgical management of midportion Achilles tendinopathy investigated open, minimally invasive, and endoscopic procedures and noted the wide range of surgical techniques, which made meaningful comparisons difficult [185]. None of the included studies involved a placebo or nonsurgical comparator. Among minimally invasive procedures (five studies), complication rates ranged from 3 to 31 percent and success rates from 69 to 100 percent.

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: Muscle and tendon injuries of the upper extremity (excluding shoulder)" and "Society guideline links: Muscle and tendon injuries of the lower extremity (excluding Achilles)".)

SUMMARY AND RECOMMENDATIONS

●Presentation and evaluation – Tendinopathy is characterized by localized pain in the affected tendon that increases with mechanical loading. It occurs most often in workers and athletes from overuse but may also occur in sedentary individuals. Most patients present after three months of symptoms. Ultrasound imaging can reveal findings that help establish the diagnosis (image 1 and image 2 and image 3).

The history should elucidate changes in training or activity (eg, frequency, duration, intensity) that may have caused the tendinopathy and determine the level of function to which the patient aims to return. Validated functional assessment scores enable the clinician to grade symptoms and determine function (figure 1 and figure 2).

Abnormal biomechanics and/or significant fluctuations in tendon loading while performing common tasks (eg, running, jumping, throwing, or typing on a keyboard) may contribute to tendinopathy. (See 'Patient assessment' above and 'Biomechanical modification' above.)

●Management – We suggest that exercise therapy, emphasizing slow, progressive, heavy-load exercise, be used to treat tendinopathy (Grade 2B). This approach is preferred to traditional physical therapy programs using less aggressive loads, medications, invasive therapies, or rest alone. A suggested treatment approach is described in the text and summarized in the following algorithm (algorithm 1). During rehabilitation, it is important to limit the volume, intensity, and rate of increase in the loads placed on the injured tendon outside of the therapeutic exercise program. (See 'Heavy-load resistance training' above and 'Activity modification and tendon load' above.)

Clinicians should be cautious with prescribing anti-inflammatory medication, including glucocorticoids. For long-term treatment of tendinopathy, glucocorticoids are potentially harmful, and we suggest they be avoided (Grade 2B). Supportive interventions may include stretching, joint mobilization, ice or heat, and appropriate orthoses. When exercise therapy alone is not successful, secondary treatment with topical nitroglycerin and extracorporeal shock wave therapy may be used. (See 'Supportive interventions' above.)

Multiple therapies for tendinopathy are under investigation but lack clear proof of efficacy. Several involve intratendinous or peritendinous injections designed to stimulate a repair response. Examples include prolotherapy and injection with autologous blood or platelet-rich plasma. (See 'Investigational treatments' above and "Biologic therapies for tendon and muscle injury".)

●Indications for surgical consultation – The initial treatment of tendinopathy consists of nonsurgical management. However, it is reasonable to obtain surgical consultation if after 6 to 12 months of diligent exercise therapy using a well-designed program in combination with activity modification and adjunct medical treatments, there has been no improvement in symptoms or function. (See 'Indications for surgery' above.)

ACKNOWLEDGMENTS — 

The UpToDate editorial staff acknowledges Alexander Scott, PhD, RPT, and Karim Khan, MD, who contributed to earlier versions of this topic review.