INTRODUCTION — Chronic pain at the lateral or medial epicondyle of the elbow is a relatively common condition, particularly among tennis players and golfers, respectively, and among manual laborers. Chronic pathologic changes in the tendon origins are associated with such pain, although the underlying causes remain unclear.
This topic will review the etiology, presentation, and management of elbow tendinopathy (formerly known as epicondylitis). Other problems associated with elbow pain and the general treatment of tendinopathy are discussed separately. (See "Evaluation of elbow pain in adults" and "Radial head subluxation (pulled elbow): Evaluation and management" and "Elbow injuries in active children or skeletally immature adolescents: Approach" and "Overview of the management of overuse (persistent) tendinopathy".)
TERMINOLOGY — The epicondyles of the elbow are bony prominences easily palpated on the medial and lateral sides of the distal humerus, proximal to the elbow joint. The lateral epicondyle of the elbow is the bony origin for the wrist extensors (figure 1); the medial epicondyle is the bony origin for the wrist flexors (figure 2). Pain at the tendon insertion or myotendinous junction of these muscle groups is referred to as lateral elbow tendinopathy (LET) and medial elbow tendinopathy (MET), respectively. LET is commonly called "tennis elbow," while MET is commonly called "golfer's elbow." Although tennis and golf can cause these injuries, so can a number of other occupational and recreational activities.
Subacute and chronic symptoms of pain and disability at the lateral and medial epicondyles often represent a tendinopathy of the respective myotendinous group and are referred to as elbow tendinopathy, as noted above. Other terms used to describe the constellation of symptoms at these locations include elbow tendinosis, elbow tendonitis, epicondylitis, and epicondylalgia. We refer to these conditions as MET and LET throughout this topic review, as these terms most accurately reflect the pathophysiology and are in common use. The pathophysiology of tendon disorders related to overuse is discussed separately. (See "Overview of overuse (persistent) tendinopathy".)
EPIDEMIOLOGY AND RISK FACTORS
General population and occupational risk factors — According to an observational study of 5871 working-age Finns, the prevalence of lateral elbow tendinopathy (LET) is 1.3 percent and medial elbow tendinopathy (MET) 0.4 percent . The overall incidence may approach 1 to 3 percent in the general population, while the incidence among patients presenting to a general medical practice is approximately 0.4 to 0.7 percent .
Smoking, obesity, age 45 to 54, repetitive movement for at least two hours daily, and forceful activity (managing physical loads over 20 kg) appear to be risk factors in the general population for the development of elbow tendinopathy [1,3]. Factors that correlate with a poorer prognosis include high physical strain at work, dominant side involvement, concomitant neck pain (with or without signs of nerve root involvement), duration of symptoms greater than three months, and severe pain at presentation [4,5].
Lateral (tennis) elbow epidemiology and risk factors — The elbow was the most commonly injured joint in a survey of 529 recreational United States Tennis Association (USTA) players, comprising approximately 20 percent of all injuries . In this study, the prevalence of elbow injuries was 10.6 injuries per 100 players (average age 46.9 years), with an incidence of 0.6 injuries per 1000 hours played.
Risk increases with age. There is a 50 percent lifetime incidence of elbow injury among club players 30 years of age or older, with higher rates in players over 40 [7,8]. The risk of injury is two to four times greater among those who play more than two hours daily , but there is no increased risk among those who play up to six hours weekly .
Only one case of LET was reported among over 700 players (including seniors) over three years at the French Open . This supports the notion that tennis elbow occurs infrequently among advanced players and is more common among recreational players, likely as a result of differences in technique. (See 'Mechanisms of injury and risk reduction' below.)
According to an electromyography study, variations in tennis racket grip size up to 0.25 inches (6.35 mm) smaller or larger than that measured by Nirschl criteria do not alter the forearm muscle firing patterns of one-handed backhands and therefore may not represent a significant risk for tennis elbow . The Nirschl criteria suggest that appropriate grip size is determined by the distance from the middle of the proximal palmar crease of the hand to the distal tip of the ring finger in inches.
Medial (golf) elbow tendinopathy epidemiology — While MET is commonly referred to as "golfer's elbow," approximately 90 percent of cases occur outside of sport participation . In particular occupational settings, notably those involving repeated forceful gripping during heavy labor, MET may affect as many as 3.8 to 8.2 percent of workers . MET is most common in the 45- to 64-year-old age group. Women are more likely than men to suffer from MET, and three of four cases involve the dominant arm.
Several sports are associated with an increased risk for MET, primarily due to repetitive forceful forearm pronation and wrist flexion. Baseball pitching is a prime example . Other sports that involve repetitive overhead throwing or forceful gripping, such as tennis, racquetball, weightlifting, and javelin, are associated with an increased risk for MET . (See "Throwing injuries of the upper extremity: Clinical presentation and diagnostic approach".)
Among golfers, elbow injuries account for 25 to 33 percent of all injuries among amateurs and 7 to 10 percent of all injuries among professionals. Of note, MET is one-third as common as LET; even among golfers, lateral elbow injuries are more common than medial injuries (ratio of 5:1) .
CLINICAL ANATOMY — Clinical anatomy of the elbow is reviewed separately; details relevant to elbow tendinopathy are discussed briefly below. (See "Evaluation of elbow pain in adults", section on 'Clinical anatomy'.)
The distal humerus has a medial and a lateral epicondyle (figure 3). The epicondyles are bony prominences easily palpated on the medial and lateral sides of the distal humerus, just proximal to the elbow joint. The lateral humeral epicondyle serves as the bony common origin of the wrist and extrinsic hand extensors; the medial humeral epicondyle serves as the bony common origin of the wrist and extrinsic hand flexors. The epicondyles are extra-articular structures.
Overuse injury involving the proximal tendons of the extensor carpi radialis brevis (felt at tip of lateral epicondyle) and occasionally the extensor digitorum communis muscle (felt just posterior and distal to tip of lateral epicondyle) constitutes lateral elbow tendinopathy (LET) (figure 1). Overuse injury involving the proximal tendons of the pronator teres and flexor carpi radialis muscles, which originate at the medial epicondyle (figure 2), causes medial elbow tendinopathy (MET).
The elbow is the articulation between the ulna and radius and the humerus (figure 4 and figure 3 and figure 5). The elbow joint is best palpated as the soft spot in the middle of a triangle formed by the lateral epicondyle, olecranon, and radial head (picture 1). Forearm pronation makes it easier to palpate the radial head.
Medial elbow stability is provided primarily by the anterior bundle of the medial collateral ligament (MCL) (figure 6). The ulnar nerve is exposed in the ulnar groove, which lies posterior and lateral to the medial epicondyle (figure 7). The ulnar nerve can be compressed just distally in the cubital tunnel.
PATHOPHYSIOLOGY — Elbow tendinopathy represents a chronic tendinosis, rather than an acute inflammatory process, involving disorganized tissue and neovessels within the involved tendon. Researchers describe the process as angiofibroblastic tendinosis; few inflammatory cells are found in these lesions . The pathophysiology of chronic, or overuse, tendinopathy is reviewed separately. (See "Overview of overuse (persistent) tendinopathy", section on 'Pathology and terminology'.)
Studies using grayscale ultrasonography and color Doppler followed by anesthetic injection show that the development of neovessels in the common extensor origin is associated with pain in lateral elbow tendinopathy (LET) . Targeting this degenerative tendinosis and neovascularization is the focus of emerging treatments. The extensor carpi radialis brevis muscle is the muscle most often involved in LET. The common flexor tendon, a conjoint sheath of the tendons of the wrist and finger flexors, is the site of injury for medial elbow tendinopathy (MET).
MECHANISMS OF INJURY AND RISK REDUCTION
General mechanisms — Repetitive athletic movements, particularly those performed rapidly and forcefully, involving eccentric motion in which a muscle-tendon unit is lengthened while under a load, may increase susceptibility to injury (this mechanism should not be confused with isolated, controlled eccentric exercises done as part of a rehabilitation program) [8,13-16]. This may occur during sport due to improper technique or equipment, or individual athletes may be susceptible due to inadequate strength, endurance, or mobility . One example is baseball pitching, in which high-energy repetitive valgus forces are exerted on the flexor-pronator mass of the forearm during late cocking and early acceleration. Once tendon damage occurs, performing further strenuous or exaggerated movements with degenerative or disorganized tissue increases the risk of further injury. Examples from tennis are described below. (See 'Physical therapy and eccentric exercise' below and 'Tennis' below.)
Occupational injuries associated with elbow tendinopathy can involve repetitive motions in which the wrist frequently deviates from a neutral position (ie, not held straight) . A dose-dependent relationship exists between the regular handling of loads over 20 kg and development of elbow tendinopathy. A significant relationship between work tasks that involve vibrating tools (eg, jackhammer) and elbow tendinopathy has yet to be demonstrated . Activity modification to limit repetitive motion, forceful tasks, and possibly vibration may reduce the risk of injury. (See 'Initial management' below.)
Tennis — A number of factors, including poor stroke mechanics and inappropriate racquet type, predispose tennis players to developing elbow tendinopathy.
Proper stroke mechanics are important to minimize the risk of elbow tendinopathy and prevent recurrence after treatment. In one observational study, instruction on stroke modification and routine conservative therapy led to a resolution of symptoms in 90 percent of tennis players with symptom duration less than six months . Correction of mechanics may require formal assessment by a tennis coach, physical therapist, or other appropriate professional.
The tennis serve provides a good example for understanding the importance of proper mechanics. Over half of the force generated for tennis serves should come from the hips and pelvis; excessive use of the wrist to generate force predisposes to injury . Subsequent upper body force generation during serves should be much less, with the shoulder contributing approximately 21 percent, the elbow 15 percent, and the wrist 10 percent. Fluid sequential transmission of force (ie, proper kinetic chain integration) from the lower to the upper body and a knee bend greater than 10 degrees mitigate shoulder and elbow torque, reducing the risk of injury . Isolation of the body's upper quarter in the performance of any overhand athletic maneuver (eg, tennis serve, baseball throw) reflects a breakdown in the smooth transfer of force from the lower to the upper body (ie, disruption in the kinetic chain).
A number of biomechanical faults increase the risk of elbow tendinopathy among tennis players and should be corrected [18,20]. Examples include the following:
●Continuous contraction of wrist extensors, insufficient follow-through, and leading with the elbow are three common faults with the beginner's backhand (picture 2). All three increase the load placed on forearm extensors.
●Excessive forearm pronation with forehand strokes or in combination with wrist snap during serves creates a sudden eccentric load on forearm extensors .
●Preparation for an advanced forehand tennis stroke often consists of a combination of extreme supination with ulnar deviation of the wrist, followed by a low-to-high trajectory, terminating with rapid and forceful wrist pronation to generate topspin (picture 3). Such extreme supination, particularly with an exaggerated grip, may theoretically increase the risk for medial elbow tendinopathy (MET).
●Excessive wrist extension either before impact or during follow-through of a backhand stroke increases the load on forearm extensors.
Use of a one-handed backhand may increase the risk of developing tennis elbow compared with a two-handed backhand, although evidence is scant . While wrist extensor activity with a one- or two-handed backhand is fundamentally the same, the added hand may limit end ranges of motion, thereby reducing abnormal elbow and forearm movement and controlling terminal wrist extension . Greater wrist extension creates additional eccentric stress during impact and early follow-through, which may account for the increased risk associated with the one-handed backhand [23,24].
No published trials demonstrate a causal relationship between racquet characteristics and the development of lateral elbow tendinopathy (LET). Nevertheless, many sports physicians and tennis professionals believe that factors such as light weight, heavy head, and inappropriately small grip size increase the forces transferred to the forearm, thereby increasing the risk of LET. Use of a racquet grip size up to but no greater than 0.25 inches (6.35 mm) smaller or larger than that determined by the Nirschl criteria is appropriate (figure 8).
Racquet shock absorbers intended to mitigate the transmission of impact forces have not been shown to reduce vibrations . Other strategies that have theoretical but unsupported utility include lowering string tension and releasing grip tightness after impact to reduce transmission of forces to the wrist and elbow. A biomechanical study in 20 recreational tennis players reported that decreased string tension produced lower peak acceleration at the elbow during a backhand stroke .
Golf — In golfers, medial elbow injuries are thought to result from traction-based insults to the elbow during the swing, usually to the trailing arm (right elbow in the right-handed golfer). The structures most often involved are the wrist and hand flexors and forearm pronators, which sustain overuse injuries at their origin on the medial epicondyle. The mechanism is thought to involve sudden deceleration of the club head, producing increased loads at the medial elbow. Often, this is due to poor swing mechanics, which may involve excessive elbow valgus at the time of impact . Such loads may also be incurred from striking the ground or other obstacles or from hitting repeatedly out of long, thick rough.
Elite golfers strike the ball with the lead wrist in flexion and the trail wrist in extension. These players may develop MET in the leading arm and LET in the trailing arm due to the stress sustained from continual practice and overuse, not poor biomechanics. However, elite golfers are less likely than amateur golfers to develop elbow tendinopathy due to their sound swing mechanics .
Conversely, amateur golfers tend to have the opposite injury pattern resulting from poor swing biomechanics. The trailing elbow develops MET, while the leading elbow develops LET. "Casting," "scooping," and "chicken winging" are common problems with the golf swing that place excessive force on the elbow and lead to injury over time:
●"Casting" occurs with an early release of the club during the down swing, and it applies added pressure on the forearm flexors of the trailing arm.
●"Scooping" occurs with early release of the wrists during the down swing before impact, causing the trail wrist to flex and lead wrist to extend.
●"Chicken winging" is when the lead arm elbow is flexed and the wrist is in extension at impact. This places excessive stress on the extensor complex of the leading arm and flexors of the trailing arm. If the plane of the club during the downswing is too steep, "chicken winging" tends to occur as it becomes necessary to maintain a square club face at impact.
More research is needed to assess the etiology of golf-related elbow injuries and develop targeted rehabilitation programs.
CLINICAL PRESENTATION AND EXAMINATION — Patients with elbow tendinopathy typically complain of extra-articular medial or lateral elbow pain. Patients may have had symptoms for only a few weeks, but others may have symptoms that persist for many months or longer. Pain severity can range from minimal, with which patients continue to participate in work or sport, to severe, interfering with even basic daily tasks and sleep. Symptoms are usually exacerbated by repetitive movements of the wrist and elbow.
The level of symptoms and pathology of the tendon can be classified as mild, moderate, or severe based on the effect on activities. In addition, the degree of pathology and stage of tendinopathy may be based on ultrasound appearance. Of note, while the chronicity of symptoms may help predict the severity of the condition, some patients may have experienced symptoms for a relatively short period and yet have late-stage tendinopathy, as determined by ultrasound findings.
Lateral elbow tendinopathy examination findings and tests — Lateral elbow tendinopathy (LET) is diagnosed clinically by the following findings:
●Localized tenderness over the lateral epicondyle and proximal wrist extensor muscle mass (picture 4)
●Pain with resisted wrist extension with the elbow in full extension (picture 5)
●Pain with passive terminal wrist flexion with the elbow in full extension (picture 6)
Other maneuvers that can be helpful for diagnosing LET include the book test and the tennis elbow test. The book test is performed by having the patient hold a reasonably heavy book in the hand of the affected upper extremity with the arm raised, elbow fully extended, and palm facing down. Discomfort at the lateral epicondyle while holding the book marks a positive test.
The tennis elbow test is performed with the patient's extended elbow stabilized in one of the clinician's hands, with the thumb of that hand placed on the patient's lateral epicondyle. The patient makes a fist, pronates the forearm, and radially deviates and extends the wrist while the clinician resists these movements at the fist. The test is positive if pain is elicited in the area of the lateral epicondyle. In the patient with more severe tennis elbow, pain may be elicited using this maneuver with the patient's elbow flexed to 90 degrees.
Pain may also be elicited with resisted wrist pronation or supination or by testing grip strength, particularly when the elbow is in full extension. However, the absence of pain elicited by these maneuvers does not preclude the diagnosis.
Medial elbow tendinopathy examination findings and tests — Medial elbow tendinopathy (MET) is diagnosed clinically by the following findings:
●Localized tenderness over the medial epicondyle (picture 7) and proximal wrist flexor muscle mass (the ulnar nerve/ulnar groove and medial collateral ligament [MCL] should not be tender)
●Pain with resisted wrist flexion (and pronation) with the elbow in full extension (picture 8)
●Pain with passive terminal wrist extension with the elbow in full extension (picture 9)
A modified version of the book test can be used to help confirm the diagnosis of MET. Instead of a book, the patient is asked to hold a 3- to 5-pound (1.4- to 2.4-kg) weight with the arm raised, elbow fully extended, and palm facing upward. Discomfort at the medial epicondyle while holding the weight marks a positive test.
The golfer's elbow test is performed with the patient's extended elbow stabilized in one of the clinician's hands, with the thumb of that hand placed on the patient's medial epicondyle. The patient makes a fist and then supinates the forearm, and ulnarly deviates and flexes the wrist, while the clinician resists these movements at the fist. A positive test is marked by pain at the medial epicondyle, possibly extending to the pronator teres and flexor carpi radialis muscles.
Pain may also be elicited with resisted wrist pronation or supination and testing of grip strength, particularly when the elbow is in full extension. However, the absence of pain elicited by these maneuvers does not preclude the diagnosis.
Approach to imaging — Diagnostic imaging is often unnecessary for the diagnosis and treatment of elbow tendinopathy in adults and non-elite athletes with classic clinical findings. However, we routinely perform musculoskeletal ultrasound (MSK US) to assess tendon integrity and pathology. Staging tendinopathy using MSK US may help to guide treatment . In addition, for any patient who manifests diminished elbow mobility, bony abnormalities, or other signs consistent with injury or intra-articular pathology, we obtain diagnostic imaging (typically three-view plain radiographs of the elbow) at the initial evaluation.
In experienced hands, MSK US can identify abnormal tendon appearance (eg, tendon thickening (image 1), partial tear at the tendon origin (image 2 and image 3), calcifications, and neovascularity when color-flow Doppler is used [29-31]). As normal tendon thickness varies among individuals, the contralateral tendon (assuming it is asymptomatic) is the best comparator to determine whether abnormal thickness is present . Increased Doppler flow is consistent with the diagnosis but not pathognomonic; absent Doppler flow should prompt investigation of alternative diagnoses. MSK US is noninvasive and often preferred by patients. MSK US can be used to localize lesions prior to surgery or to guide injections. (See "Musculoskeletal ultrasound of the elbow".)
For patients with symptoms that have persisted for three to six months or who experience severe or worsening symptoms despite appropriate initial management, we generally obtain a standard three-view elbow series of plain radiographs, including an axial view if posterior elbow pain is present. This allows us to assess for fractures, osteoarthritis, and other bony injuries (eg, loose bodies). The axial view is used to evaluate posterior osteophytes and calcifications within the tendons.
Magnetic resonance imaging (MRI) may help clinicians to determine whether surgery is needed for treatment of chronic, recalcitrant symptoms of six months or longer duration, and what procedure to perform . The presence of intermediate or high T2 signal intensity within the common flexor tendon and the presence of peritendinous soft tissue edema were the most specific findings of medial elbow tendinopathy (MET) when compared with asymptomatic elbows in a small observational trial .
Additional ultrasound resources — Instructional videos demonstrating proper performance of the ultrasound examination of the elbow and related pathology can be found at the website of the American Medical Society for Sports Medicine: lateral elbow, medial elbow, sports US pathology. Registration must be completed to access these videos, but no fee is required.
DIAGNOSIS — Elbow tendinopathy is primarily a clinical diagnosis made on the basis of a suggestive history, consistent examination findings, and possibly confirmatory findings using musculoskeletal ultrasound (MSK US). Patients typically describe pain localized to either of the epicondyles that developed over weeks to months and describe performing repetitive wrist movements regularly during sport or work. Examination reveals focal tenderness at the origin of either the wrist flexors that is exacerbated by full, passive wrist extension (medial elbow tendinopathy [MET]), or the wrist extensors that is exacerbated by full, passive wrist flexion (lateral elbow tendinopathy [LET]). Ultrasound may reveal tendon thickness, partial tears, and neovascularity.
DIFFERENTIAL DIAGNOSIS — A number of conditions can cause focal medial or lateral elbow pain (table 1 and table 2). A focused history and examination, including a few special maneuvers when suggested by the history, can be used to differentiate among potential alternative diagnoses. General evaluation of the patient with elbow pain is discussed separately. Below, several conditions that may be confused with elbow tendinopathy in particular clinical settings are described. (See "Evaluation of elbow pain in adults".)
●Limited or painful elbow motion ‒ Intra-articular effusions or painful elbow motion suggests intra-articular pathology. Pain with forceful, active terminal extension of the elbow may represent posterior osteoarthritis or valgus extension overload, which is seen in overhand athletes. Osteochondritis dissecans of the olecranon fossa can also cause pain with forceful terminal elbow extension in overhead athletes. In contrast, passive joint motion does not cause pain in patients with elbow tendinopathy, and tenderness is focal at the tendon origin of either the medial or lateral epicondyle. (See "Throwing injuries of the upper extremity: Clinical presentation and diagnostic approach", section on 'Valgus extension overload (VEO) syndrome' and "Osteochondritis dissecans (OCD): Clinical manifestations, evaluation, and diagnosis".)
●Acute elbow trauma ‒ A history of blunt trauma (eg, fall onto elbow) suggests the possibility of a fracture. Elbow plain radiographs should be obtained in such instances to evaluate for gross and subtle injuries, such as a radial head fracture, or to look for a fat pad sign (image 4) suggesting fracture. Ligaments may also be damaged in such trauma, and varus and valgus stress maneuvers of the elbow should be performed to assess collateral ligament integrity.
●Radiating elbow pain ‒ Neurologic conditions can cause unilateral elbow pain. Compression of the posterior interosseous nerve in the radial tunnel (ie, radial tunnel syndrome) often causes tenderness a few centimeters distal to the lateral epicondyle. This condition may occur concomitantly with lateral elbow tendinopathy (LET). Compression of the ulnar nerve in the cubital tunnel (ie, cubital tunnel syndrome) often causes tenderness just distal to the medial ulnar groove. Pain or paresthesias from ulnar neuritis can be elicited by tapping over the ulnar nerve at the ulnar groove (ulnar nerve Tinel's sign) or by placing the elbow in full flexion (elbow flexion test). Pain elicited by the Spurling maneuver suggests cervical radiculopathy, which can cause elbow pain. In contrast to the pain associated with elbow tendinopathy, pain from nerve compression or neuritis typically radiates along the course of the nerve and produces a burning or "electric" sensation. In addition, tenderness from elbow tendinopathy is focal at the tendon origin, rather than over the nerve. (See "Overview of upper extremity peripheral nerve syndromes" and "Clinical features and diagnosis of cervical radiculopathy".)
●Medial elbow pain in overhead athlete — Baseball pitchers and, more rarely, tennis and other overhead athletes can sustain an injury to the ulnar collateral ligament (UCL) of the elbow. This causes medial elbow pain predominately over the joint line, but pain may also be felt along the medial epicondyle, potentially causing confusion with medial elbow tendinopathy (MET). (See "Throwing injuries of the upper extremity: Clinical presentation and diagnostic approach", section on 'Ulnar collateral ligament (UCL) injury'.)
The patient with UCL injury experiences less pain with resisted elbow flexion but demonstrates a positive milking maneuver. The milking maneuver (picture 10) places valgus stress on the medial (ie, ulnar) collateral ligament (MCL) of the elbow in a throwing position. Pain elicited by the test suggests MCL insufficiency in throwers and overhead athletes, although the characteristics of this test are not well studied . The book test (described above) is positive in patients with epicondylitis but not those with a UCL elbow injury. (See 'Clinical presentation and examination' above.)
●Diffuse muscle pain ‒ Diffuse muscle tenderness in atypical patterns in patients with chronic symptoms may represent a myofascial pain complex. In contrast, patients with elbow tendinopathy complain of focal pain, and tenderness is limited to the origin of the involved tendon. (See "Overview of soft tissue rheumatic disorders".)
Overview of treatment and algorithm — Once a clinical diagnosis of elbow tendinopathy is made, our initial treatment consists of the following:
●Activity modification (reduction or abstinence from inciting activities)
●Counterforce bracing (some patients prefer compression sleeve)
●Oral analgesics: acetaminophen, nonsteroidal antiinflammatory drugs (NSAIDs) if not contraindicated
●Physical therapy, including wrist mobility and eccentric strength exercises
●Ice applied to affected epicondyle area after provocative activity
An algorithm outlining our treatment approach is provided (algorithm 1). These initial steps are discussed immediately below; persistent or worsening pain despite appropriate management often prompts imaging and additional therapies. (See 'Antiinflammatory treatments' below and 'Secondary management' below.)
Systematic reviews of randomized trials of the management of lateral elbow tendinopathy (LET) reveal a wide range of treatment options but little high-quality evidence supporting any particular approach [35-37]. Most trials had significant limitations, including inadequate study design, high risk of bias, small sample size, and limited statistical analysis. The management approach discussed below is based upon these limited studies and our clinical experience.
Observation — If left untreated, symptoms associated with elbow tendinopathy persist between six months and two years . For patients who can function adequately without intervention or who prefer conservative management, a "wait and see" approach may be reasonable. These patients must understand that rest alone may not lead to a resolution of symptoms and a recovery period of months to years may be necessary.
Modification of activity and biomechanics — Patients should try to avoid activities that exacerbate symptoms. For athletes, correction of faulty mechanics must be part of their activity modification. (See 'Mechanisms of injury and risk reduction' above.)
Bracing — As part of our initial management of elbow tendinopathy, we apply a counterforce brace, which applies pressure just distal to the common extensor tendon origin, thereby reducing the forces transferred to the tendon origin (picture 11). Counterforce bracing may provide benefit during the first six weeks following injury  and is easy to use and inexpensive. These braces are placed on the forearm approximately 2 to 3 cm distal to the point of maximal tenderness (just distal to the lateral epicondyle) .
In a systematic review of the use of braces in elbow tendinopathy, limited data prevented the authors from drawing firm conclusions . Nevertheless, counterforce bracing may reduce tendon and muscle strain at the origin of the forearm extensor muscles, thereby relieving pain and improving function. In our experience, many patients prefer a simple compression sleeve, which is a reasonable option.
A controlled, observational, manufacturer-sponsored study of extensor carpi radialis brevis and extensor digitorum communis activity using electromyelograms (EMGs) found that the application of a counterforce brace with an air-filled bladder significantly reduced muscle activity proximal to the brace . No such reduction was found in patients treated with a standard counterforce brace or no brace.
No significant differences in outcome were found at 26 and 52 weeks in one clinical trial in which patients were randomly assigned to initial treatment using a counterforce brace alone, physical therapy alone, or a combination of bracing and therapy . Over the first six weeks, physical therapy led to better pain and disability scores than bracing alone. No placebo group was included.
Other types of braces are being developed, but evidence of their effectiveness is scant. A small, manufacturer-supported trial of a dynamic extensor brace found improved function and reduced pain for up to 24 weeks among patients randomly assigned to treatment with the brace and standard care compared with those receiving standard care alone . Particularly for tennis players who wish to continue playing, a compression sleeve worn around the elbow may provide support and reduce symptoms .
Splints — Some clinicians use volar splints to reduce activity of the wrist extensors and flexors during particularly painful episodes of elbow tendinopathy. We do not recommend splinting except in the most severe cases. Splinting was not found to be more effective than counterforce bracing in a small randomized trial . A multicenter, retrospective cohort study involving 4614 workers diagnosed with elbow tendinopathy found that patients treated with splints had higher rates of limited duty, more medical visits, higher charges, and longer durations of treatment than those managed without splints .
Physical therapy and eccentric exercise — We have found well-designed physical therapy programs to be effective initial treatment for many patients with elbow tendinopathy. Effective programs include progressive eccentric and isometric strengthening, incorporating flexibility training and other modalities as needed [2,16,45-47]. Eccentric exercise is the application of a load to a muscle as it is lengthening (picture 12 and picture 13). Application of this technique for elbow tendinopathy involves holding a weight or applying a taut resistance band with the wrist extended and then allowing the wrist extensors to lengthen against the resistance provided by the weight or band. A sample rehabilitation program used in the author's clinic is provided (table 3).
Despite our clinical experience, studies of eccentric exercise programs show mixed results. A systematic review of 23 randomized controlled trials involving physical therapy for LET found insufficient evidence to demonstrate benefit . We believe inconsistencies in methodologic quality and the wide range of approaches to physical therapy in the studies reviewed account for this conclusion.
A number of studies in conditions such as Achilles' tendinopathy suggest that daily eccentric isokinetic strengthening exercises provide effective treatment for chronic tendinopathy. Extrapolating from such studies, some researchers advocate this rehabilitative approach for elbow tendinopathy, and we believe such exercises should be included in the physical therapy program. A systematic review of 12 studies (8 randomized trials) involving 334 patients with LET found the available evidence to be limited in quality but concluded that "the majority of consistent findings support the inclusion of eccentric exercise" as part of treatment . (See "Achilles tendinopathy and tendon rupture" and "Overview of the management of overuse (persistent) tendinopathy", section on 'Heavy-load resistance training'.)
In one of the better controlled studies of this approach, researchers randomly assigned patients with chronic LET to either standard physical therapy or standard therapy plus an isokinetic eccentric strengthening program for the forearm supinators and wrist extensors . Patients in the eccentric training group demonstrated marked reductions in pain within one month, less disability, and greater improvement in tendon appearance on ultrasound compared with patients treated with standard physical therapy. Upon completion of the program, patients in the eccentric training group had no strength deficit of their wrist extensors and forearm supinators compared with the unaffected side. A similar, albeit smaller, trial reported significantly better outcomes in patients assigned to perform eccentric strengthening with a specially designed rubber bar (picture 14) compared with patients who followed a standard physical therapy program without eccentric exercises .
Standard physical rehabilitation of upper extremity sports injuries includes core strengthening and sports-specific movement exercises (picture 15). Although few supporting trials exist, we advocate this approach.
SECONDARY MANAGEMENT — In patients who do not improve with standard initial interventions, we often obtain imaging studies before resorting to other treatments such as injections or other alternative therapies. An alternative diagnosis revealed by imaging is managed as indicated; persistent elbow tendinopathy can be managed with continued conservative treatment including physical therapy, antiinflammatory agents, nontraditional modalities, or surgical referral (algorithm 1).
Determining the stage of tendinopathy using ultrasound may help determine which treatment options are most suitable:
●Patients with low-grade tendinopathy based on ultrasound findings typically require only basic interventions such as load reduction, eccentric strengthening exercises, and a counterforce brace (algorithm 1).
●Patients with more severe tendinopathy may need additional interventions. If not contraindicated, nitroglycerin patches, and possibly more effective dosing of standard analgesics, may reduce symptoms and improve compliance with strengthening exercises.
●Patients with severe tendinopathy may not respond adequately to basic interventions or may feel that recovery is too protracted and may seek other treatment options, such as ultrasound-guided tenotomy, iontophoresis, or injection of biologic therapies (eg, platelet-rich plasma [PRP]).
●Surgical referral is generally reserved for patients with severe symptoms or larger tendon tears that do not improve despite careful compliance with a well-designed physical therapy program, and possibly other interventions, for longer than six months.
Antiinflammatory treatments — Antiinflammatories have been a mainstay of the treatment of elbow tendinopathy for many years, although supporting evidence consists of anecdotal success and a few limited studies. As the scientific understanding of tendinopathy has developed, controversy surrounding the role of antiinflammatory medications in the treatment of elbow tendinopathy and other chronic degenerative tendinopathies has grown. Examples of antiinflammatory treatment include icing, nonsteroidal antiinflammatory drugs (NSAIDs), iontophoresis, and glucocorticoid injection. Ice in combination with an eccentric strength and flexibility program was no better than eccentric training alone for lateral elbow tendinopathy (LET) . (See 'Pathophysiology' above.)
Nonsteroidal antiinflammatory drugs — Although evidence is limited, a systematic review found that NSAIDs may reduce pain and improve function in the short-term (ie, six weeks) . We try to limit both the amount and duration of NSAID therapy, given the potential side effects of NSAIDs and our understanding of the pathophysiology of tendinopathy (see 'Pathophysiology' above). Topical NSAIDs (eg, diclofenac gel) may have limited benefit in acute elbow tendinopathy, but studies are preliminary .
Glucocorticoid injections — Multiple trials and systematic reviews have found that glucocorticoid injection for LET improves many short-term (six-week) outcome measures [53-55] but does not prevent recurrence and may lead to worse long-term outcomes [45,55-60]. For short-term relief of severe symptoms, a single (ideally ultrasound-guided peri-tendinous) glucocorticoid injection (picture 16) is a reasonable treatment option when used as part of a comprehensive management program including physical therapy. We do not advocate multiple injections or long-term treatment with glucocorticoid injections. Injections for medial elbow tendinopathy (MET) pose a theoretical risk due to the proximity of the ulnar nerve, but when performed by clinicians experienced with the procedure and using ultrasound guidance, complications are rare.
There are a few short-term clinical scenarios in which we are willing to perform a glucocorticoid injection. Examples may include a tennis player who wants to compete in a tournament or a physical laborer who needs to keep working but is hampered by pain. In such instances, the clinician should clearly describe the potential risks and benefits of the treatment and engage the patient in a frank discussion. The working assumption for both parties should be that the injection is performed for short-term relief while physical therapy is performed to enable a long-term cure.
Trials of glucocorticoid injection in elbow tendinopathy are limited [54,61]. In a typical study, 198 patients with LET of at least six weeks duration without prior treatment were randomized to eight sessions of standard physical therapy, glucocorticoid injections, or observation . Patients in the glucocorticoid group showed the greatest improvement in symptoms at six weeks but had high rates of recurrence at 52 weeks. Moreover, the glucocorticoid group performed significantly worse on all outcome measures in long-term follow up.
Another study of glucocorticoid injection involved a "peppering" technique in which the painful tendon is punctured approximately 40 to 50 times . The 120 patients in this study were randomly assigned to receive injections of 1 mL triamcinolone plus 1 or 2 mL of lidocaine. Most patients had excellent results at one year regardless of the medication or dose, suggesting that the technique of injection played an important role. The researchers speculate that the "peppering" technique promotes a beneficial inflammatory response. (See 'Secondary management' above.)
Investigational treatments of possible benefit — A number of potential treatments for elbow tendinopathy are under study and reflect the changing understanding of the pathophysiology of tendinopathy. The mechanism for many of these treatments is not clearly understood. Tissue growth factors may play a role in some therapies. Other treatments are described as "proinflammatory." Theoretically, proinflammatory treatments address disorganized tendon patterns, neovessels, and degenerative changes by stimulating an inflammatory response (table 4). Many of these trials are of limited quality [61,63].
The mechanical and medicinal interventions described below are the subject of ongoing research. Small, preliminary clinical trials suggest they provide benefit in some patients.
Topical nitroglycerin — Nitric oxide may stimulate collagen synthesis by wound fibroblasts. Topical application of nitroglycerin (glyceryl trinitrate) in chronic tendinopathies theoretically improves tendon healing by this mechanism. This hypothesis was tested in a controlled trial of 86 patients with chronic LET treated with standard physical therapy and either a transdermal nitroglycerin patch or a placebo patch. The nitroglycerin group demonstrated clinical improvements in symptoms and function throughout the six-month course of the study . One additional trial supports the use of topical nitroglycerin, but further study of this proposed treatment is needed .
Ultrasound-guided percutaneous needle tenotomy — Needle tenotomy involves injecting local anesthetic and then using a needle under ultrasound guidance to fenestrate tendinotic tissue, break up calcifications, and (if needed) abrade the surface of underlying bone. The mechanism underlying this proposed technique remains unclear. Patients then perform passive stretching and standard physical therapy strengthening exercises at home or under the guidance of a physical therapist.
Studies of needle tenotomy for elbow tendinopathy are of limited quality . In an observational, uncontrolled trial of the protocol described, 55 patients with chronic elbow tendinopathy despite standard conservative treatment reported good or excellent outcomes at an average of 28 months . Another uncontrolled study of 20 patients with chronic LET treated with this technique reported 100 percent patient satisfaction and a 90 percent reduction of hypoechoic scar tissue at six months . At three-year follow-up, no patient had required further treatment, including surgery.
Iontophoresis — Studies of iontophoresis are small and preliminary, but the technique may provide some short-term benefit. In one randomized, controlled trial, patients treated with dexamethasone by iontophoresis noted significant improvement of symptoms at two days compared with placebo, but this benefit was lost at one month . Phonophoresis and iontophoresis with topical naproxen showed similar benefits in pain and function scores in patients with elbow tendinopathy . No studies have compared topical NSAIDs with topical steroids in elbow tendinopathy.
Investigational treatments of unproven benefit
Platelet-rich plasma and other biologic injections — The use of biologic therapies such as platelet-rich plasma (PRP) injection for the treatment of musculoskeletal conditions is discussed separately; studies directly related to the management of elbow tendinopathy are discussed below. (See "Biologic therapies for tendon and muscle injury".)
Given the limitations of available evidence as discussed below and the significant variations in products and protocols used in research trials, we believe that PRP and similar therapies should not be used as primary therapy for LET. Use should be reserved for well-designed randomized trials to identify potential subgroups who may benefit and possibly for secondary treatment of recalcitrant cases.
PRP is purported to contain growth factors that stimulate tissue repair, and percutaneous injection of PRP is used by some clinicians to treat elbow tendinopathy. However, in systematic reviews of studies of PRP in the treatment of chronic LET, the majority of randomized trials found that PRP was ineffective [71,72]. One review of randomized and quasi-randomized trials, 25 of which involved PRP, concluded that PRP injections "probably provide little or no clinically important benefit for pain or function" . While a smaller systematic review and network meta-analysis (10 studies) looking at treatment with PRP, autologous blood, or glucocorticoid injection reported relative improvements in pain following treatment with PRP and autologous blood, these findings were limited by the small number of high-quality studies .
The inconsistent results of individual trials are demonstrated by the following examples:
●A randomized trial of 60 patients with chronic LET (symptoms for minimum of three months) reported no significant difference in the reduction of pain or disability at three months in patients treated with PRP compared with those treated with glucocorticoid or placebo (saline) . In addition, PRP injection did not have a notable effect upon the ultrasound appearance of the involved tendons. The intended one-year follow up was not possible due to the large number of patients in all groups who dropped out of the study.
●A randomized trial of 230 patients with chronic LET reported no difference in pain scores at 12 weeks but significant improvements in pain scores and elbow tenderness at 24 weeks in patients treated with PRP injection compared with those not administered PRP .
●A randomized trial of 100 patients with chronic LET reported that patients treated with PRP injection had significant and sustained improvement in function compared with those treated with a glucocorticoid injection [76,77]. Both groups received physical therapy involving an eccentric strengthening program, and function was measured using a validated assessment tool. However, these studies did not include a placebo arm and were funded in part by a manufacturer of the centrifuge used to obtain PRP.
In refractory cases of elbow tendinopathy, autologous blood injection is another treatment option that involves injecting a sample of the patient's blood under ultrasound guidance into the site of chronic elbow tendinosis. Some small controlled and observational studies of patients with refractory MET and LET who received ultrasound-guided autologous blood injection plus dry-needling have reported improvements in symptoms and in the ultrasound appearance of involved tendons [78,79]. In a randomized, blinded trial of 30 patients with chronic LET, autologous blood injections were found to elicit improvements at six months comparable to those achieved with saline plus lidocaine or glucocorticoid injections. Other studies report no significant improvement , and overall, studies are of limited quality . The relative importance of the inflammatory response stimulated by the blood and dry-needling or growth factors present in the blood remains unclear, as does the effectiveness of this treatment. A meta-analysis of studies comparing autologous blood and glucocorticoid injection for LET found that glucocorticoid provided better immediate pain relief (2 to 4 weeks) but autologous blood products led to improved function and decreased pain and disability during the intermediate period (6 to 24 weeks) .
Extracorporeal shockwave therapy and other electrophysical modalities — Acoustic waves have been used to treat chronic LET. Overall, evidence supporting extracorporeal shockwave therapy (ESWT) and other "electrophysical" modalities is unconvincing, and we do not recommend it . The procedure is generally uncomfortable, and although studies exist that suggest ESWT provides some benefit , several studies have failed to do so [83,84].
Acupuncture — Systematic reviews of studies of acupuncture in the treatment of lateral elbow pain have found insufficient evidence to determine whether the technique is effective [85,86]. Results from a few small randomized trials suggest acupuncture may provide some short-term relief, but there is no evidence of sustained benefit. Further study is needed. The role of acupuncture for analgesia is discussed separately. (See "Acupuncture".)
Botulinum injection — Injection of botulinum toxin A at the myotendinous junction is another purported means of stimulating an inflammatory response for treatment of tendinopathy. However, botulinum injection is not a standard treatment, and clinicians should exercise caution as it can cause weakness of finger and wrist extensors.
●In one randomized, controlled trial of botulinum, patients with chronic, refractory elbow tendinopathy treated with botulinum toxin A experienced a reduction in their symptoms compared with those receiving placebo . No difference in grip strength was detected. An anticipated side effect of the botulinum toxin A injection (transient weakness in middle finger extension) did occur in some patients at two weeks but resolved. Recurrence rates and long-term outcome were not reported.
●A randomized trial of 48 patients involved botulinum injections at a location one-third the length of the forearm measured from the lateral epicondyle, along the course of the posterior interosseus nerve. Pain relief at rest was greater for the group treated with botulinum toxin compared with placebo. However, grip strength did not differ between groups, and weakness of the third and fourth fingers in patients injected with botulinum toxin A persisted up to 16 weeks .
Prolotherapy — This treatment for chronic tendinopathy involves injection of a local irritant to elicit an inflammatory response. Numerous case reports and a small number of controlled trials suggest that prolotherapy may be effective in some chronic musculoskeletal injuries . In a double-blinded, controlled trial of 24 adults with chronic LET, patients randomly assigned to treatment with prolotherapy experienced reduced pain and improved extensor and grip strength . The role of prolotherapy in the treatment of elbow tendinopathy warrants further investigation.
●Sclerosing polidocanol injection ‒ Neovascularity associated with chronic tendinopathy is thought to contribute to pain. Sclerosing polidocanol injections under ultrasound guidance are an investigational procedure meant to target neovessels and reduce pain. An uncontrolled pilot study of 11 patients with chronic LET treated with a single injection of polidocanol into the extensor tendon origin with signs of neovascularity found improvement in patients' pain scores and maximal grip strength up to eight months following injection .
●Autologous tenocyte injection ‒ This investigational procedure is intended to promote healing in chronic, severe LET through the injection of autologous tenocytes. Only small case series describing the treatment have been published to date, and further research is needed [92,93].
INDICATIONS FOR ORTHOPEDIC REFERRAL — Over 90 percent of cases of elbow tendinopathy can be managed nonoperatively . The most severe, recalcitrant cases that have failed to respond to many months of nonoperative management, including good compliance with a well-designed physical therapy program, may warrant surgical evaluation. We prefer to emphasize physical therapy and avoid surgical referral for twelve months . (See 'Physical therapy and eccentric exercise' above.)
Indications for orthopedic referral include:
●Severe pain or marked dysfunction for a minimum of six months but generally longer
●Failure of conservative management, including properly performed physical therapy, to improve symptoms or function over twelve months
●Patient uninterested in pursuing nonoperative treatment options (eg, alternative treatments described above) for chronic tendinopathy
Studies of surgical management are scant, but one retrospective, single-center review of all patients treated operatively for lateral elbow tendinopathy (LET) found no difference in outcome among patients treated using open, arthroscopic, or percutaneous surgical approaches . Conservative care averaged 13.2 months in each group prior to surgery. Studies suggest that patients with residual histologic tendinopathy after arthroscopic debridement have poorer outcomes .
RETURN TO SPORT OR WORK — The goal of elbow tendinopathy treatment is a pain-free, functional return to work or sport. Some patients may be able to return to work so long as aggravating activities can be avoided. Secondary gain may play a role in some patients with occupational injuries [4,5].
Improper tennis stroke mechanics can contribute to injury in the recreational tennis player . The patient must receive instruction and demonstrate proper mechanics before returning to full participation. We routinely refer recreational tennis and golf players to professional coaches to assess their stroke mechanics. High-level tennis players seldom develop elbow tendinopathy, suggesting that mechanical flaws play a role in the condition for many non-elite players. A slow functional progression of tennis or golf exercises allows for a safer return to sport following rehabilitation and is generally recommended prior to resuming competition. Sample programs for return to play are provided (table 5 and table 6). (See 'Mechanisms of injury and risk reduction' above.)
Some athletes can continue playing in a modified fashion while undergoing rehabilitation, provided they continue to improve. This approach is reasonable in players who experience pain only after matches. Modified play may include switching to a two-handed backhand, reducing string tension, and eliminating shots with exaggerated spin. Some players require complete rest from inciting activities during rehabilitation to ensure recovery.
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: Chronic tendon injury and tendinopathies" and "Society guideline links: Muscle and tendon injury".)
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 5th to 6th 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 10th to 12th 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: Elbow tendinopathy (tennis and golf elbow) (The Basics)")
●Beyond the Basics topic (see "Patient education: Elbow tendinopathy (tennis and golf elbow) (Beyond the Basics)")
SUMMARY AND RECOMMENDATIONS
●Pathophysiology – Elbow tendinopathy represents a chronic tendinosis at the origin of the wrist flexors or extensors. It is not an acute inflammatory process. Pathologically, it is characterized by disorganized tissue and neovessels. (See 'Epidemiology and risk factors' above and 'Pathophysiology' above.)
●Risk factors – Increased age, repetitive wrist movement for at least two hours daily, and forceful activity (managing physical loads over 20 kg) comprise the major risk factors for elbow tendinopathy in the general population. Among tennis players, poor stroke mechanics and inappropriate racquet type predispose to elbow tendinopathy. Elbow tendinopathy in golfers is related to overuse and poor stroke mechanics. (See 'Mechanisms of injury and risk reduction' above and 'Tennis' above and 'Golf' above.)
●Clinical presentation – Patients with elbow tendinopathy typically complain of extra-articular medial or lateral elbow pain associated with specific findings:
•Medial elbow tendinopathy (MET; "golf elbow") ‒ Tenderness at origin of wrist flexor tendons at medial epicondyle; pain exacerbated by passive wrist extension; pain exacerbated by resisted wrist flexion
•Lateral elbow tendinopathy (LET; "tennis elbow") ‒ Tenderness at origin of wrist extensor tendons at lateral epicondyle; pain exacerbated by passive wrist flexion; pain exacerbated by resisted wrist extension
(See 'Clinical presentation and examination' above.)
●Treatment – High-quality evidence supporting specific treatments for elbow tendinopathy (elbow tendinosis) is scant. Once a clinical diagnosis is made, our initial treatment consists of activity modification, counterforce bracing, nonsteroidal antiinflammatory drugs (NSAIDs) if not contraindicated, and physical therapy (algorithm 1). Counterforce bracing may reduce tendon and muscle strain at the origin of the forearm extensor muscles, thereby relieving pain and improving function. Well-designed physical therapy programs that include progressive eccentric strengthening are effective treatment for many patients with elbow tendinopathy. (See 'Initial management' above and 'Physical therapy and eccentric exercise' above.)
Glucocorticoid injection for LET improves many short-term (six-week) outcome measures and enables patients to engage in physical therapy but does not prevent recurrence and may lead to worse long-term outcomes. Topical nitroglycerin is a safe treatment that improves symptoms for some patients. (See 'Glucocorticoid injections' above and 'Topical nitroglycerin' above.)
In patients who do not improve with standard initial interventions, we often obtain imaging studies before resorting to other treatments. A number of potential therapies for tendon healing are under study and may provide benefit for some patients, but evidence is limited. Options include percutaneous needle tenotomy and iontophoresis. (See 'Investigational treatments of possible benefit' above.)
●Indications for referral – Indications for orthopedic referral include severe pain or marked dysfunction for six months or longer and failure of conservative management to improve symptoms or function over six months. (See 'Indications for orthopedic referral' above.)
ACKNOWLEDGMENT — The author wishes to acknowledge the assistance of Casey Wagner, MD, who provided invaluable insights into the pathomechanics of golf-related medial elbow tendinopathy (MET) and related materials used in the topic.