Evaluation of elbow pain in adults

INTRODUCTION — Elbow pain may be due to disorders involving the joint itself, the surrounding soft tissue structures, or a referred source (eg, neck, shoulder, or wrist). Joint and soft tissue structures that are common sources of pain include the epicondyles and their tendon attachments (medial and lateral), the olecranon bursa, and the radial, median, and ulnar nerves, which course near the elbow joint. Referred pain most commonly arises from a cervical radiculopathy or from the shoulder.

This topic will discuss how to approach the adult patient with nontraumatic elbow pain systematically and identify the most common causes for such pain. Discussions of specific conditions and traumatic injuries affecting the elbow are found separately. (See "Elbow tendinopathy (tennis and golf elbow)" and "Elbow fractures and dislocation in adults" and "Overview of upper extremity peripheral nerve syndromes".)

CLINICAL ANATOMY — The elbow joint is formed by the articulation of the distal end of the humerus with the proximal radius (radial head) and ulna (figure 1 and figure 2 and figure 3 and figure 4). Flexion/extension occurs at the ulnohumeral joint and is powered by the biceps (figure 5) and triceps (figure 6) muscles, respectively. The normal arc of motion ranges from full extension (0 degrees) to full flexion (135 degrees). Some individuals demonstrate the ability to extend the elbow beyond normal; this condition is referred to as "cubitus recurvatus" or cubital recurvatum (picture 1). This condition may occur in isolation or stem from a hypermobility connective tissue disorder. (See "Clinical manifestations and diagnosis of hypermobile Ehlers-Danlos syndrome and hypermobility spectrum disorder".)

Supination-pronation (rotation) occurs at the radiohumeral and proximal radioulnar articulations of the elbow joint. The biceps muscle supinates and the pronator teres muscle pronates the elbow. The elbow can rotate from 0 to 180 degrees.

The epicondyles are bony prominences easily palpated on the medial and lateral sides of the distal humerus, proximal to the elbow joint, and they are a common source of pain. The tendinous origin of the muscles that flex and extend the wrist and fingers are located at the medial and lateral epicondyle, respectively.

Multiple bursae have been identified around the elbow joint; the olecranon bursa is the most superficial, and swelling of this bursa is both common and easily observed (picture 2).

A number of ligaments support the elbow joint; clinically important is the ulnar collateral or medial ligamentous group that assists in providing valgus stability (figure 7). The anterior bundle or band runs from the medial humeral condyle to the coronoid process of the ulna and provides the principal resistance to valgus stress. A second clinically important structure is the annular ligament, which is a component of the lateral collateral ligament complex and a major stabilizer of the proximal radioulnar joint. 

The ulnar nerve courses through the elbow joint in the ulnar groove posterior and medial to the elbow (figure 1 and figure 8). Its course is contiguous with the joint capsule; thus, any process that distends the joint tends to impinge upon the ulnar nerve, causing paresthesias in the ulnar aspect of the hand and occasional weakness in the flexor digiti quinti. The median nerve runs anteromedial to the joint capsule and in close proximity to the brachial artery (figure 3); entrapment in this region typically is due to elbow trauma, repetitive elbow flexion, or supination and pronation of the forearm. The radial nerve passes posterior to the humerus, and then ascends anteriorly over the lateral epicondyle before dividing into superficial and deep branches in the forearm (figure 3). (See "Overview of upper extremity peripheral nerve syndromes".)

ETIOLOGY AND COMMON PRESENTATIONS — Many of the common causes of elbow pain are periarticular, including epicondylitis (inflammation or degeneration of underlying tendons), olecranon bursitis, nerve entrapment syndromes, and referred pain. Systemic diseases (eg, rheumatoid arthritis) usually have polyarticular involvement that is revealed by a careful musculoskeletal history and examination. However, oligoarticular involvement can occur, as in the seronegative spondyloarthritides. (See "Clinical manifestations of rheumatoid arthritis" and "Clinical manifestations and diagnosis of peripheral spondyloarthritis in adults" and "Reactive arthritis" and "Clinical manifestations and diagnosis of psoriatic arthritis".)

Patients who are experiencing a problem unique or intrinsic to the elbow typically present with complaints of pain (eg, epicondylitis or tendinopathy), swelling (eg, olecranon bursitis), or a loss of motion (eg, joint injury). Each of the more common presentation patterns is discussed below.

Lateral elbow pain — Lateral elbow pain is the most common complaint at the elbow. The source of pain may be the lateral epicondyle and the common extensor tendon origin, the radiohumeral joint, or referred pain from the shoulder or neck. A more complete list of the causes of lateral elbow pain is found in the table (table 1).

●The pain of lateral epicondylitis (tennis elbow) is typically well localized (the patient often points to the lateral epicondylar region) and is aggravated by activity that contracts the wrist extensors, including repetitious use of the forearm and wrist, and shaking hands. (See "Elbow tendinopathy (tennis and golf elbow)".)

●Pain arising from the elbow (radiohumeral) joint is located slightly more posterior to the epicondyle (between the epicondyle and the olecranon process), is not well localized, and is readily distinguished from the pain of lateral epicondylitis by its effect upon joint motion (it is exceedingly rare for lateral epicondylitis to affect elbow range of motion). A joint effusion reduces elbow extension.

●Pain referred to the lateral elbow is suggested by the absence of increased pain with palpation or elbow movement, a vague description, and aggravation of the pain with provocative movement of the shoulder or neck.

Medial elbow pain — Medial elbow pain is the second most common complaint at the elbow. It frequently arises either from the medial epicondylar region or the ulnar nerve as it travels through the cubital tunnel. A more complete list of the causes of medial elbow pain is found in the table (table 2).

●As with lateral epicondylitis, the pain of medial epicondylitis is well localized and is aggravated by actions that contract the wrist flexors and pronators, such as lifting or repetitious use of the forearm and wrist. (See "Elbow tendinopathy (tennis and golf elbow)".)

●Pain arising from the ulnar nerve is suggested by radiation into the ulnar side of the hand and associated sensory (or occasionally motor) symptoms in the fourth and fifth fingers. (See "Overview of upper extremity peripheral nerve syndromes".)

Elbow swelling — Patients who complain of elbow swelling most often have olecranon bursitis, however, other more serious conditions may occur. The warmth and redness that accompany the swelling, and the rapidity with which symptoms and signs develop, are clues to distinguish among potential underlying causes (usually trauma, sepsis, or gout). The ability of the patient to extend and flex the elbow completely generally excludes an intra-articular process as the cause of the elbow pain.

Impaired range of motion — Patients with an intraarticular process occasionally complain of elbow swelling as well as elbow pain. However, these symptoms are virtually always overshadowed by their universal complaint, "I cannot straighten my elbow." Causes of synovitis include rheumatoid arthritis, seronegative spondyloarthropathies, such as reactive arthritis, psoriasis, or inflammatory bowel disease, crystal-induced synovitis due to gout or pseudogout, and septic bacterial arthritis.

Loss of smooth elbow motion without signs of inflammation occurs almost exclusively in athletes, particularly throwers (eg, baseball players), boxers, and gymnasts, who sustain trauma to the joint through repetitive throwing, punching, or upper extremity loading, respectively. This presentation, in particular in an adolescent athlete, can suggest the presence of osteonecrosis (osteochondritis dissecans) of the humerus. (See "Osteochondritis dissecans (OCD): Clinical manifestations, evaluation, and diagnosis".)

Referred pain — Cervical radiculopathy and shoulder pathology, particularly rotator cuff tendinopathy and shoulder instability, may refer pain to or "through" the elbow [1]. Such pain is typically a deep ache that is not affected by elbow motion. These diagnoses are suggested by associated symptoms (paresthesias or hypesthesias) and signs, possibly including focal weakness and the absence of local tenderness and swelling at the elbow, in addition to aggravation of symptoms with shoulder or neck movement.

As an example, lateral herniation between C6-7 produces pain at the shoulder blade, pectoral area, and medial axilla with radiation to posterolateral upper arm, dorsal elbow and forearm, index and medial digits or all of the fingers, and sensory impairment in these areas. There is also weakness in extension of the forearm and sometimes the wrist and diminished or absent triceps reflex. (See "Evaluation of the adult patient with neck pain".)

HISTORY — A careful history should be performed prior to the examination. The history should seek to identify an acute versus a chronic complaint, and detail a mechanism of injury (eg, traumatic or secondary to overuse) if one occurred. The onset of the injury and a history of prior interventions (eg, surgeries, rehabilitative therapy, and injections) may offer important insights into etiology.

Indolent pain with no specific history of injury, and symmetric involvement of both elbows, should prompt consideration for rheumatoid arthritis. The pain is frequently described as dull and throbbing and may be associated with some loss of motion. (See "Clinical manifestations of rheumatoid arthritis".)

Critical to the diagnosis is an assessment of any functional impairment compared to baseline, including any sport-related or occupational dysfunction, and any limitations of activities of daily living. The history should include arm dominance, and conditions and interventions affecting the entire kinetic chain, particularly proximal structures (eg, neck, shoulder, and scapular stabilizers).

PHYSICAL EXAMINATION — High quality studies of techniques commonly used to examine the elbow are lacking [2]. A systematic review of 10 studies of the diagnostic accuracy of examination maneuvers (24 in total) used for assessing elbow conditions concluded that none of the described tests provided adequate certainty to rule in or rule out a specific condition [2]. Nine of the 10 studies included in the review had a high or unclear risk of bias. Nevertheless, observational evidence and clinical experience suggest that a careful examination can aid diagnosis [3].

Efficient examination of the elbow involves a systematic approach, including inspection, palpation, range of motion assessment, motor and sensory evaluation, special tests, and examination of related areas. The elbow, remainder of the affected upper extremity, and cervical spine should be examined. Key diagnostic findings are described in the table (table 3):

Inspection — The examination of the elbow begins with systematic inspection. Look for joint swelling, discoloration, atrophy (picture 3), hypopigmentation, nodules, and asymmetry. The carrying angle (humerus to ulna; normal is 5 to 15 degrees) should be noted, paying close attention to any angular deformities and asymmetries.

Inspect the olecranon bursa for swelling and thickening. If the bursa is noted to be enlarged, flex the elbow to 90 degrees and palpate for ballotable cystic swelling (picture 4). An acutely swollen, warm, and erythematous bursa suggests the diagnosis of acute bursitis, while a swollen and thickened bursa is consistent with a flare of chronic bursitis; a thickened bursa alone, without swelling, suggests chronic bursitis. Fluid should be aspirated to determine the underlying cause of swelling if there is associated pain, local inflammation, or if the patient is febrile.

Palpation — Palpate the radiohumeral joint to determine the presence of an effusion or focal tenderness. The lateral and medial epicondylar regions are palpated for tenderness with the elbow flexed at 90 degrees (picture 5 and picture 6). Local tenderness is the hallmark feature of lateral and medial epicondylitis, respectively. Patients with pain in one of these areas should go on to have confirmatory special testing as outlined below.

While not directly palpable, the general locations of the medial and lateral collateral ligaments are palpated for tenderness in patients, particularly throwing athletes, suspected of ligamentous injury. (See 'Ligamentous injury' below.)

The insertion of the triceps tendon and olecranon are palpated for tenderness, particularly in patients with posterior elbow pain.

If present, nodules of rheumatoid arthritis are varied in size, generally subcutaneous, circular in shape, firm, and non-tender (picture 7).

Range of motion — Elbow motion should be assessed; normal values are provided in the table (table 4). Elbow flexion, extension, pronation, and supination should be tested.

Passive range of motion testing of the ulnohumeral joint assesses the integrity of the elbow in flexion and extension (picture 8). Full arm extension and flexion are compared side to side.

Full elbow extension dramatically reduces the intraarticular volume of the joint. With an inflammatory synovitis, the elbow joint assumes a position of flexion in order to increase the joint volume, thereby reducing the intraarticular pressure and associated pain felt within the elbow. Thus, full elbow extension will cause pain with an elbow synovitis, but not with olecranon bursitis.

Loss of full extension with end-point stiffness suggests the presence of a small effusion with mild arthritis. Loss of full extension AND flexion suggests the presence of a large effusion with moderate to severe arthritis. A joint effusion related to either an inflammatory arthritis or hemarthrosis can be readily excluded by documenting normal range of motion.

Osteoarthritis of the elbow is uncommon, unless there is a history of elbow fracture or repetitive loading of the upper extremity. A fracture involving the elbow is uncommon in patients who are able to perform full elbow extension [4,5].

Passive range of motion of the radiohumeral joint assesses the integrity of the elbow in supination and pronation (picture 9). Passive supination and pronation are compared side to side while palpating the radial head.

Loss of full supination or pronation suggests previous fracture or dislocation of the elbow or osteonecrosis. Loss of full supination also occurs with congenital dislocation of the radial head. Pronation and supination are painful and limited in patients with synovitis; this may help to distinguish patients with a joint effusion from those with bursal swelling, as olecranon bursitis is associated with normal joint motion.

Elbow instability — The elbow is tested for laxity with the joint in both 0 and 30 degrees of flexion [6]. This is done by placing one hand behind the elbow with the thumb and middle finger over the location of the medial and lateral collateral ligaments (just distal to the epicondyles), while the other hand holds the patient's wrist and exerts a valgus and varus stress [7]. The degree of joint laxity and quality of the endpoint is compared with the unaffected elbow.

Motor and sensory examination — Motor function is evaluated by assessing active motion and strength, including resisted elbow flexion, extension, pronation, and supination. Note any asymmetry or pain. The median (figure 9), ulnar (figure 10), and radial (figure 11) nerves all cross the elbow joint and their sensation should be assessed; this examination is described separately. (See "Overview of upper extremity peripheral nerve syndromes".)

Special tests

●Lateral epicondylitis (tennis elbow or Cozen) test — The tennis elbow test is performed with the patient's extended elbow stabilized in the physician's hand and the thumb of that hand positioned on the patient's lateral epicondyle. The patient makes a fist, pronates the forearm and radially deviates and extends the wrist while the physician applies a resisting force at the fist (picture 10). The test is positive if pain is elicited in the area of the lateral epicondyle. In the patient with more advanced tennis elbow, pain is elicited when the same maneuver is performed with the elbow flexed to 90 degrees. (See "Elbow tendinopathy (tennis and golf elbow)", section on 'Lateral elbow tendinopathy examination findings and tests'.)

The "book test" may be used to help diagnose tennis elbow. It is performed by having the patient hold a book with the affected arm in full extension and pronation (palm down). A positive test is marked by pain at the lateral epicondyle.

●Medial epicondylitis (golf elbow) test — The golf elbow test is the inverse of the tennis elbow test. Pain is elicited by the clinician applying resistance to wrist flexion and forearm supination (picture 11) and is felt in the region of the medial epicondyle and pronator teres and flexor carpi radialis muscles. (See "Elbow tendinopathy (tennis and golf elbow)", section on 'Medial elbow tendinopathy examination findings and tests'.)

●Radial tunnel syndrome "middle finger test" — The diagnosis of radial tunnel syndrome, involving entrapment of the radial nerve as it enters the supinator muscle, should be considered in patients initially diagnosed with tennis elbow who fail to improve with conservative therapy. Flexion force applied against long finger (third digit) extension distal to the proximal interphalangeal joint may provoke pain over the extensor muscle mass in the proximal forearm. This finding is suggestive of radial tunnel syndrome, which is often misdiagnosed as resistant lateral tennis elbow.

●Tinel sign — In patients with suspected ulnar nerve entrapment, tapping a finger over the ulnar groove or cubital tunnel may reproduce the patient’s symptoms (positive Tinel sign) (picture 12). A positive sign elicited at the medial elbow usually consists of lancinating pain or numbness felt in the fourth (ring) and fifth (little) fingers; the response should be distinctly different from the opposite side. Abnormal responses can be confirmed with nerve conduction velocity testing. (See "Overview of upper extremity peripheral nerve syndromes".)

A positive Tinel sign may be present in radial tunnel syndrome or median nerve entrapment due to pronator syndrome in the proximal forearm.

●Hook test — This test assesses for integrity of the distal biceps tendon (picture 13) and is described in detail separately. (See "Biceps tendinopathy and tendon rupture", section on 'Distal biceps tendon evaluation'.)  

Examination of related areas — The neck, shoulder and wrist should be examined carefully in the patient with elbow pain. This examination excludes elbow symptoms secondary to referred pain or resulting from compensation for dysfunction or injury at remote locations (eg, tennis elbow secondary to rotator cuff dysfunction). (See "Physical examination of the shoulder" and "Evaluation of the adult patient with neck pain" and "Evaluation of the adult with subacute or chronic wrist pain".)

Examination pearls

●Normal range of motion testing of the elbow effectively rules out involvement of the elbow joint itself. This is particularly important when it is not clear if the source of swelling is bursal or intraarticular.

●Epicondylitis and olecranon bursitis rarely affect elbow range of motion. The only exceptions to this rule are cellulitis accompanying a septic olecranon bursitis or chronic lateral epicondylitis in the patient with an extremely low pain threshold. Any loss of full extension or flexion reflects involvement of the elbow joint.

DIFFERENTIAL DIAGNOSIS

Epicondylitis — Epicondylitis (medial or lateral) has numerous etiologies including repetitive wrist turning or hand gripping, tool use, shaking hands, or twisting movements that may exceed tissue capacity. It is an occupational hazard in carpenters, gardeners, dentists, and politicians. Tennis players, particularly novices with a one-handed backhand, often suffer lateral epicondylitis as a result of pressure grip strain, or due to backhand shots performed with a "leading elbow" in which the elbow is pointed to the net during racquet impact with the ball. Medial epicondylitis has been referred to as "golfer's elbow." (See "Elbow tendinopathy (tennis and golf elbow)".)

Lateral epicondylitis is a degenerative overuse process of the extensor carpi radialis brevis and the common extensor tendon. A presumptive diagnosis requires:

●Local tenderness directly over the lateral epicondyle

●Pain aggravated by resisted wrist extension and radial deviation

●Pain aggravated by strong gripping or decreased grip strength

●Normal elbow range of motion

Medial epicondylitis is much less common than lateral epicondylitis. It is a degenerative overuse process of the flexor carpi radialis tendon. A presumptive diagnosis requires:

●Local tenderness directly over the medial epicondyle

●Pain aggravated by resisted wrist flexion and ulnar deviation

●Pain aggravated by strong gripping or decreased grip strength

●Normal elbow range of motion

Olecranon bursitis — The olecranon bursa, at the posterior point of the elbow, has a synovial membrane that may be affected by gout, rheumatoid arthritis, sepsis, hemorrhage, or trauma (picture 2 and picture 4). Traumatic bursitis accounts for most cases. Common traumatic etiologies include leaning on the elbow or using the elbow to arise from bed or as part of an occupation such as laying carpet. The onset is seldom acute when trauma is the inciting cause, and the surrounding tissues are usually normal.

Infection of the bursa usually follows an abrasion or occurs in association with an initial cellulitis. Involvement of the olecranon bursa may be the initial presentation of gout, but it most commonly occurs with recurrent episodes of gouty arthritis. (See "Clinical manifestations and diagnosis of gout".)

The diagnosis of acute olecranon bursitis is readily made by noting the characteristic swelling over the posterior olecranon process (picture 2). As this swelling does not involve the joint, it does not prevent the patient from fully extending the elbow, a movement that will reduce the pain. However, bursal aspiration and laboratory analysis may be necessary to distinguish a suspected septic or metabolic cause from traumatic swelling.

Triceps tendinopathy — The triceps muscle is the primary extensor of the elbow. While uncommon, tendinopathy of the triceps insertion is occasionally seen in weight lifters or laborers whose work involves repetitive elbow extension against resistance. Diagnosis is generally straightforward in the setting of a suggestive history and examination findings. On examination, patients report pain at the posterior elbow with resisted elbow extension, and tenderness at the triceps insertion. (See "Overview of the management of overuse (persistent) tendinopathy".)

Nerve entrapment — The ulnar, radial, and median nerves course in close proximity to the elbow. Any disease process affecting the elbow can involve these nerves or their branches and cause sensory or motor symptoms in the hand. (See "Overview of upper extremity peripheral nerve syndromes".)

Ulnar neuropathy is the most common compression neuropathy affecting the elbow. In mild cases, symptoms include sensory loss and paresthesias over the ring and small fingers. In more severe cases, weakness of the interossei becomes apparent, and the patient may complain of a weakened grip and clumsiness with the hand. (See "Ulnar neuropathy at the elbow and wrist".)

Both the median and radial nerves can be compressed secondary to overuse. In pronator teres syndrome, the median nerve is compressed in the proximal forearm secondary to repetitive grasping or pronation movements, producing signs and symptoms comparable to carpal tunnel syndrome. (See "Overview of upper extremity peripheral nerve syndromes", section on 'Pronator teres syndrome'.)

In radial tunnel syndrome, sometimes referred to as recalcitrant tennis elbow, the deep branch of the radial nerve can become entrapped as it enters the radial tunnel under the edge of the supinator muscle, creating pain 4 to 5 centimeters distal to the lateral epicondyle. (See "Overview of upper extremity peripheral nerve syndromes", section on 'Radial nerve syndromes'.)

Elbow joint inflammation due to rheumatoid arthritis rarely causes an entrapment neuropathy of either the anterior interosseous nerve, a pure motor branch of the median nerve, or the posterior interosseous nerve, a pure motor branch of the radial nerve. In the anterior interosseous syndrome, there is motor dysfunction of the flexor pollicis longus and of the flexor digitorum profundus of the index and middle fingers; there is no sensory loss in the hand, but a paresthetic pain may be felt in the elbow and over the proximal volar aspect of the forearm [8]. The posterior interosseous nerve syndrome is associated with a deep-seated pain within the elbow and weakness upon extension of the third, fourth, and fifth digits [9]. (See "Overview of upper extremity peripheral nerve syndromes", section on 'Anterior interosseous neuropathy' and "Overview of upper extremity peripheral nerve syndromes", section on 'Posterior interosseous neuropathy'.)

Osteoarthritis — The elbow is a non-weight bearing joint. Thus, degenerative processes are exceptionally rare [10]. When present, osteoarthritis is usually related to prior intraarticular fractures, avulsion injuries to the humeral condyles ("Little League" elbow), or previous episodes of osteonecrosis [11]. Nevertheless, the presence of an elbow deformity generally should be interpreted as strong evidence for an underlying inflammatory arthritis. (See "Throwing injuries of the upper extremity: Clinical presentation and diagnostic approach", section on 'Little League elbow' and "Clinical manifestations and diagnosis of osteoarthritis".)

Ligamentous injury — Primarily in throwing athletes, injury can occur to the supporting ligaments of the elbow, particularly the ulnar (ie, medial) collateral ligament. Great force is generated during the late cocking and early acceleration phases of throwing (eg, pitching a baseball or serving a tennis ball), which results in valgus stress on the elbow, born primarily by the ulnar collateral ligament. Repetitive throwing can create cumulative microtrauma to this ligament resulting in medial elbow pain and possibly ligamentous laxity. Throwing-related elbow injuries, including ulnar collateral ligament strain, common flexor tendon sprain, and valgus extension overload, are discussed separately. (See "Throwing injuries of the upper extremity: Clinical presentation and diagnostic approach", section on 'Elbow injuries'.)

Distal biceps tendon rupture — The distal biceps tendon attaches to the radial tubercle just distal to the radial head. Its major function is to supinate the forearm but it also serves as a secondary elbow flexor. Injury to the tendon can occur from either forceful lifting or supination and causes sudden pain. The pain, which is felt deep in the antecubital fossa, is often vaguely described in quality and location. Swelling and ecchymosis is often present in the antecubital fossa. The diagnosis is suggested by the history and by the presence of tenderness over the radial tubercle, deep in the antecubital fossa, a positive hook test, and pain that is aggravated by resisting flexion and supination of the forearm. The presentation, evaluation, and diagnosis of distal biceps tendon rupture is discussed in greater detail separately. (See "Biceps tendinopathy and tendon rupture".)

Congenital dislocation of the radial head — Older adolescents and young adults sometimes complain of snapping of the lateral elbow. Examination may reveal an abnormal valgus carrying angle of the elbow and a loss of full supination. These individuals may have congenital dislocation of the radial head, which can be assessed with standard radiographs. This is the most common congenital condition of the elbow and often remains asymptomatic for years [12].

Osteochondritis dissecans of the humeral capitellum — Osteochondritis dissecans (OCD) is a non-inflammatory degeneration of subchondral bone of the capitellum of the humerus. OCD is thought to be the result of excessive compressive forces and repetitive microtrauma and is most commonly identified in adolescent athletes engaged in overhead throwing or upper extremity weight-bearing (eg, gymnasts). Patients with capitellar OCD typically present with a history of persistent or worsening lateral elbow pain relieved by rest, clicking of the joint, and flexion contractures in severe cases. Examination typically reveals tenderness over the capitellum and lateral elbow; the elbow is optimally flexed to best palpate the capitellum. OCD may be missed on plain radiographs, and advanced imaging (magnetic resonance imaging) may be needed to establish the diagnosis. (See "Osteochondritis dissecans (OCD): Clinical manifestations, evaluation, and diagnosis".)

DIAGNOSTIC IMAGING

Plain radiographs — Radiographs of the elbow are rarely necessary in patients with nontraumatic elbow pain (image 1 and image 2A-B). However, patients with a significant loss of elbow motion or function, or who have sustained significant trauma to the elbow, generally warrant imaging with plain radiographs [13]. Osteoarthritis of the elbow is uncommon outside of the setting of previous trauma or underlying congenital bony abnormalities. Loss of joint space and the presence of osteophytes between the humerus and the pseudoarticulation of the ulna and radius on plain film are consistent with a diagnosis of osteoarthritis (image 3A-B).

Ultrasound — As many injuries and pathologic conditions of the elbow involve relatively superficial structures, musculoskeletal ultrasound (US) is often a valuable tool for assessing elbow pain. US is a reliable tool for diagnosing lateral epicondylitis, the most common elbow injury [13,14]. US examination of the elbow is reviewed in detail separately (see "Musculoskeletal ultrasound of the elbow"); the structures amenable to examination are listed below by location [15]:

●Anterior elbow – Brachialis and brachioradialis muscles, distal biceps tendon (figure 5), radial (figure 12 and figure 11) and median nerves (figure 9), brachial artery (figure 3), and anterior joint capsule.

●Medial elbow – Common wrist flexor tendon (figure 13 and figure 14 and figure 15) and ulnar collateral ligament (figure 7 and figure 16).

●Posterior elbow – Posterior elbow joint, triceps tendon insertion, olecranon bursa, cubital tunnel, and ulnar nerve (figure 8 and figure 15).

●Lateral elbow – Common wrist extensor tendon (figure 17 and figure 18), radiocapitellar joint, and radial head (figure 4).

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: anterior elbow ultrasound examination, sports US elbow pathology, US guided interventional procedures of the elbow. Registration must be completed to access these videos, but no fee is required.

CONFIRMATORY TESTS — A number of confirmatory tests may be warranted in patients with a suspected diagnosis based upon the above findings.

Olecranon bursa aspiration — When the bursa has accumulated fluid that is detectable by palpation, the fluid should be aspirated if there is pain, local inflammation, or fever (picture 14). Bursal fluid should be sent for culture and Gram stain. A white blood cell count should be obtained and the fluid examined for the presence of crystals.

●A bursal fluid white blood cell count of more than 1000/mm³ is suggestive of inflammation from infection, rheumatoid arthritis, or gout. (See "Septic bursitis", section on 'Obtaining bursal samples'.)

●The identification of crystal is helpful in establishing the diagnosis of gout. (See "Clinical manifestations and diagnosis of gout" and "Clinical manifestations and diagnosis of calcium pyrophosphate crystal deposition (CPPD) disease".)

Radiohumeral joint aspiration — Aspiration of the radiohumeral joint is indicated in patients with a history and physical examination that are suspicious for joint effusion to differentiate traumatic hemarthrosis from inflammatory arthritis, to diagnose crystal-induced arthritis, and to detect the rare case of septic arthritis (picture 15). Involvement of the elbow with bacterial arthritis is unusual relative to other joints (eg, the knee, wrists, ankles, and hips). However, early diagnosis and therapy are important to preserve joint function. (See "Septic arthritis in adults".)

Diagnostic injections

Suspected lateral or medial epicondylitis — Patients with a suggestive history and lateral or medial epicondylar tenderness should have testing to confirm the diagnosis of lateral or medial epicondylitis, respectively. Local anesthetic block may be necessary to sort out difficult cases. The diagnosis and management of epicondylitis is reviewed separately. (See "Elbow tendinopathy (tennis and golf elbow)".)

Radial tunnel syndrome — A lidocaine (Xylocaine) block can be helpful in diagnosing radial tunnel syndrome. The technique helps to confirm the diagnosis if it relieves pain and is accompanied by a temporary deep radial palsy, and when an injection given at another time but more proximally in the region of the lateral epicondyle does not relieve the patient's symptoms. One standard approach is to inject one mL of one percent lidocaine four finger-breadths distal to the lateral epicondyle. (See "Overview of upper extremity peripheral nerve syndromes", section on 'Radial nerve syndromes'.)

Electromyography — Electromyography and nerve conduction studies are used to evaluate suspected nerve compression syndromes. Although these studies can be helpful in confirming a diagnosis, they are somewhat insensitive [16]. (See "Overview of electromyography" and "Overview of nerve conduction studies".)

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)".)

SUMMARY AND RECOMMENDATIONS

●Clinical anatomy – Elbow pain may be due to disorders involving the joint itself or surrounding structures, such as the epicondyles (medial and lateral) and their related structures (ligaments; origin of wrist flexors and extensor muscles), olecranon bursa, distal biceps tendon, and the radial and ulnar nerves. Referred pain may arise from the neck (cervical radiculopathy) or shoulder. (See 'Clinical anatomy' above.)

●Etiology and common presentations – Lateral elbow pain is the most common complaint at the elbow (table 1). The source may be the lateral epicondyle, radiohumeral joint, or referred pain. Medial elbow pain is the second most common complaint (table 2), and frequently arises either from the medial epicondyle or the ulnar nerve as it travels through the cubital tunnel. Patients who complain of elbow swelling most often have olecranon bursitis. Limited elbow motion suggests an intra-articular process.

Potential diagnoses based on the location of symptoms and the presentation are described in the section on etiology (table 3) (see 'Etiology and common presentations' above), while greater detail about each of the common and important diagnoses is provided in the section on differential diagnosis. (See 'Differential diagnosis' above.)

●Physical examination – Efficient examination of the elbow includes inspection, range of motion testing, and palpation of the following structures (table 3):

•Lateral epicondyle and extensor tendons

•Medial epicondyle and flexor tendons

•Radiohumeral joint

•Olecranon bursa

Normal range of motion of the elbow effectively rules out involvement of the elbow joint itself. More specific tests that are performed based on the history and preliminary findings to establish a diagnosis are described in the text. (See 'Physical examination' above and 'Confirmatory tests' above.)

●Diagnostic imaging – Radiographs of the elbow are usually unnecessary in patients with nontraumatic pain. Musculoskeletal ultrasound (US) is often a valuable tool for assessing the elbow, as many structures are relatively superficial. (See 'Diagnostic imaging' above.)

ACKNOWLEDGMENTS — The UpToDate editorial staff acknowledges Ron Anderson, MD and Bruce Anderson, MD, who contributed to earlier versions of this topic review.