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Joints may simply be painful (arthralgia) or also inflamed (arthritis), with redness, warmth, and swelling. Pain may occur only with use or also at rest, and there may or may not be fluid within the joint (effusion).

A useful initial distinction is whether pain is present in one joint (monarticular) or multiple joints (polyarticular). When multiple joints are affected, different terms can be used:

• Arthritis involving ≤ 4 joints, particularly when it occurs in an asymmetric fashion, is oligoarticular or pauciarticular arthritis.
• Arthritis involving > 4 joints, usually in a symmetric fashion, is polyarticular arthritis.

Pathophysiology

Polyarticular arthralgia can originate from arthritis or from extra-articular disorders (eg, polymyalgia rheumatica, fibromyalgia). Pain caused by intra-articular disorders may be secondary to an inflammatory arthritis (eg, infection, RA, crystal deposition) or a noninflammatory process (eg, osteoarthritis).

Inflammatory arthritis may involve peripheral joints only (eg, hands, knees, feet) or both peripheral and axial joints (eg, sacroiliac, apophyseal, discovertebral, costovertebral).

Etiology

Peripheral oligoarticular and polyarticular arthritis have specific, likely causes (see Table 5: Approach to the Patient With Joint Disease: Some Causes of Polyarticular Joint Pain); the presence or absence of axial involvement helps limit possibilities. However, in many patients, arthritis is often transient and resolves without diagnosis or may not fulfill the criteria for any defined rheumatic disease.

Acute polyarticular arthritis is most often due to the following:

• Infection (usually viral)
• Flare of a rheumatic disease

Chronic polyarticular arthritis in adults is most often due to the following:

• RA (inflammatory)
• Osteoarthritis (noninflammatory)

Chronic polyarticular arthritis in children is most often due to the following:

• Juvenile idiopathic arthritis

Table 5
Some Causes of Polyarticular Joint Pain Cause Suggestive Findings Diagnostic Approach* Polyarticular disorders† Acute rheumatic fever Fever, cardiac symptoms and signs, and migrating inflammation of the large joints, usually starting in the legs and migrating upward Can occur 2–6 wk after streptococcal pharyngitis Specific clinical criteria (Jones criteria), antistreptolysin O titers, group A streptococcal antigen testing Hemoglobinopathies (eg, sickle cell disease or trait, thalassemias) Symmetric pain in joints of hands and feet Bone pain, avascular necrosis Young patients of African or Mediterranean descent, often with known diagnosis Hb electrophoresis Juvenile idiopathic arthritis Oligoarticular symmetric arthritis during childhood, with or without signs of iridocyclitis, generalized adenopathy, splenomegaly, or unexplained fever ANA and RF testing Lyme disease arthritis Erythema migrans, fever, malaise, headache, and myalgias in days to weeks after tick bite (causes monarticular arthritis in later stage of disease) Serologic testing for antibodies against Borrelia burgdorferi Other rheumatic diseases (eg, polymyositis/dermatomyositis, scleroderma, Sjögren's syndrome, polymyalgia rheumatica) Depends on specific rheumatic disease and can include specific dermatologic manifestations, dysphagia, muscle soreness, or dry eyes and dry mouth X-ray and various serologies (eg, ANA, RF testing, anti-SS-A, anti-SS-B, anti-Scl-70) Sometimes skin or muscle biopsy Psoriatic arthritis Psoriasis, dactylitis (sausage digits), tendinitis, onychodystrophy Clinical evaluation Sometimes x-ray RA Symmetric involvement of small and large joints (particularly involvement of the PIP joints, MCP joints, or wrist joints) with ulnar deviation of the fingers, subcutaneous nodules, boutonnière and swan-neck deformities, carpal tunnel syndrome More prevalent among women Specific clinical criteria, x-ray, anti-CCP, and RF testing Septic arthritis (a small proportion of bacterial arthritides are polyarticular, particularly that caused by Neisseria gonorrhea) Acute, severe pain; redness; swelling May be difficult to distinguish from crystal arthropathy Higher index of suspicion in patients with risk factors for STDs Arthrocentesis Serum sickness Fever, arthralgia, lymphadenopathy, and skin eruption 1–21 days after treatment with a biologic compound (eg, blood products, vaccines, protein concentrates) Clinical evaluation SLE Malar rash, oral ulcers, alopecia, history of serositis (eg, pleuritis pericarditis), RA-like polyarthralgia Usually women Serologic testing (eg, ANA, RF, anti-dsDNA) Systemic vasculitis (eg, giant cell arteritis, Henoch-Schönlein purpura, hypersensitivity vasculitis, polyarteritis nodosa, Wegener's granulomatosis) Various and sometimes vague extra-articular symptoms, including abdominal pain, renal failure, sinonasal pathology, and dermatologic lesions (eg rash, ulcers, purpura, nodules) ESR Biopsy of any suspected affected area (eg, kidney, skin) Viral arthritis (particularly parvovirus but also enterovirus, adenovirus, Epstein-Barr, coxsackievirus, cytomegalovirus, rubella, mumps, hepatitis B, hepatitis C, varicella, HIV) Less severe than septic arthritis Malaise, lacy red malar rash, concomitant anemia in patients with parvovirus infection Jaundice with hepatitis B Systemic lymphadenopathy with HIV Arthrocentesis Sometimes parvovirus serologies or other virologic testing based on clinical suspicion Oligoarticular disorders Ankylosing spondylitis‡ Back pain and symmetric involvement of the large joints, iritis, tendinitis, aortic insufficiency More common among young adult males X-ray HLA-B27 Behçet's syndrome Oral and genital ulcers, sometimes eye pain Begins in the 20s Specific clinical criteria Crystal-induced arthritis§ (eg, uric acid, Ca pyrophosphate, Ca hydroxyapatite) Acute onset of severe pain, redness, swelling (particularly in the great toe or knee for uric acid deposition) Arthrocentesis Fibromyalgia Diffuse myalgias, tender muscular points not involving joints, fatigue, sometimes irritable bowel syndrome Usually women Specific clinical criteria (see Fig. 1: Bursa, Muscle, and Tendon Disorders: Diagnosing fibromyalgia) Infective endocarditis Fever, malaise, weight loss, heart murmur, embolic phenomena Blood cultures ESR Transesophageal echocardiography Osteoarthritis‡ Chronic pain usually in lower extremity joints, PIP and DIP joints, 1st carpometacarpal joint Heberden's nodes, Bouchard's nodes X-ray Reactive and enteropathic arthritis‡ Acute, asymmetric joint pain predominantly involving the lower extremities 1–3 wk after GI or GU infection (chlamydial urethritis) Clinical evaluation Sometimes X-ray, STD testing, stool cultures *Patients with joint effusion or inflammation should have arthrocentesis (with cell counts, Gram stain, cultures, and crystal examination), and usually ESR. X-rays are often unnecessary. †Also may manifest as oligoarticular. ‡Can manifest with axial involvement. §Most often monarticular, but sometimes oligoarticular. ANA = Antinuclear antibodies; CCP = cyclic citrullinated peptide; DIP = distal interphalangeal; dsDNA = double-stranded DNA; MCP = metacarpophalangeal; PIP = proximal interphalangeal; RF = rheumatoid factor; STD = sexually transmitted disease.

Evaluation

Evaluation should determine whether the joints or periarticular structures are the cause of symptoms and whether there is inflammation or effusion. If inflammation is present or the diagnosis is unclear, symptoms and signs of systemic disorders should be sought.

History: History of present illness should identify the acuity of onset (eg, abrupt, gradual), temporal patterns (eg, diurnal variation, persistent vs intermittent), chronicity (eg, acute vs longstanding), and exacerbating factors (eg, cold weather, activity). Patients should be specifically asked about unprotected sexual contact (possible gonococcal infection) and tick bites or residence in a Lyme-endemic area.

Review of systems should seek symptoms and signs of causative disorders (see Table 5: Approach to the Patient With Joint Disease: Some Causes of Polyarticular Joint Pain and Table 6: Approach to the Patient With Joint Disease: Some Suggestive Findings in Polyarticular Joint Pain).

Past medical history and family history should identify known rheumatic disorders and other conditions capable of causing joint symptoms (see Table 5: Approach to the Patient With Joint Disease: Some Causes of Polyarticular Joint Pain).

Physical examination: Vital signs are reviewed for fever.

Examination of the head, neck, and skin should note any signs of conjunctivitis, iritis, mucosal lesions, sinonasal abnormalities, lymphadenopathy, ecchymoses, skin ulcers, psoriatic plaques, purpura, or malar rash.

Cardiopulmonary examination should note any signs of acute inflammatory disease or serositis (eg, murmur, pericardial rub, muffled heart sounds, bibasilar dullness consistent with pleural effusion).

Genital examination should note any discharge, ulcers, or other findings consistent with sexually transmitted diseases.

Musculoskeletal examination should note muscular point tenderness associated with fibromyalgia. Joint examination begins with inspection for deformities, erythema, swelling, or effusion and then proceeds to palpation and estimation of pain and crepitus with active and passive range of motion. Comparison with the contralateral unaffected joint often helps detect more subtle changes. Examination should note whether the distribution of affected joints is symmetric.

Periarticular structures also should be examined for discrete, soft swelling at the site of a bursa (bursitis), point tenderness at the insertion of a tendon (tendinitis), and point tenderness over a tendon with fine crepitus (tenosynovitis).

Red flags: The following findings are of particular concern:

• Hot, swollen, red joints
• Any extra-articular symptoms (eg, fever, skin rash, plaques, ulcers, conjunctivitis, iritis, murmur, purpura)

Interpretation of findings: An important initial element is whether pain originates in the joints, spine, or both or in other structures such as bones, tendons, bursae, muscles, other soft-tissue structures, or nerves (see Table 6: Approach to the Patient With Joint Disease: Some Suggestive Findings in Polyarticular Joint Pain). Pain that worsens with active rather than passive joint motion may indicate tendinitis or bursitis; intra-articular inflammation generally restricts active and passive range of joint motion severely. Tenderness or swelling at only one side of a joint, or away from the joint line, suggests an extra-articular origin (eg, in ligaments, tendons, or bursae); findings on several aspects of the joint suggest an intra-articular cause. Pain that is diffuse and described inconsistently or vaguely may result from fibromyalgia or functional disorders.

If the joints, spine, or both are involved, differentiating inflammatory from noninflammatory disorders may help. Clinical findings of prominent morning stiffness, nontraumatic joint swelling, and fever or weight loss are suggestive of an inflammatory disorder, but testing is often helpful.

Examination of the hand joints may yield other clues (see Table 6: Approach to the Patient With Joint Disease: Some Suggestive Findings in Polyarticular Joint Pain) and may help differentiate osteoarthritis from RA (see Table 7: Approach to the Patient With Joint Disease: Differential Features of the Hand in RA and Osteoarthritis).

Back pain with arthritis suggests ankylosing spondylitis a reactive or psoriatic arthritis, or fibromyalgia.

Table 6
Some Suggestive Findings in Polyarticular Joint Pain Finding Possible Cause General findings Bone tenderness or chest pain Sickle cell crisis Coexisting tendinitis Gonococcal or rheumatoid disease Conjunctivitis, abdominal pain, and diarrhea Reactive arthritis Fever and malaise Infection, gout, rheumatic disorders, vasculitis Malaise and lymphadenopathy Acute HIV infection Oral and genital ulcer Behçet's syndrome Raised silver plaques Psoriatic arthritis Recent pharyngitis and migrating joint pain Rheumatic fever Recent vaccination or blood product Serum sickness Skin ulcerations, rash, and abdominal pain Vasculitis Tick bites Lyme arthritis Urethritis Gonococcal or reactive arthritis Hand findings (see also Table 7: Approach to the Patient With Joint Disease: Differential Features of the Hand in RA and Osteoarthritis) Asymmetric involvement of the fingers Reactive or psoriatic arthritis Asymmetric DIP joint involvement plus tophi Chronic gout DIP joint involvement with pitting in the adjacent nail and slightly asymmetric involvement of other joints Psoriatic arthritis PIP, DIP, and sometimes 1st MCP involvement Heberden's nodes, Bouchard's nodes Osteoarthritis Raynaud's syndrome Progressive systemic sclerosis, SLE, or mixed connective tissue disease Scaling erythema over the extensor joint surfaces, especially over the knuckles Dermatomyositis Sore, painful hands with few objective abnormalities SLE and, less often, dermatomyositis Swan-neck or boutonnière deformities RA Thickening of the skin and flexion contractures Progressive systemic sclerosis DIP = distal interphalangeal; MCP = metacarpophalangeal; PIP = proximal interphalangeal.

Table 7
Differential Features of the Hand in RA and Osteoarthritis Criteria RA Osteoarthritis Character of swelling Synovial, capsular, soft tissue; bony only in late stages Bony with irregular spurs; occasional soft cysts DIP involvement Not usual, except in thumb Usual MCP involvement Usual Unusual If present, consider hemochromatosis PIP involvement Usual Frequent Tenderness Usual None or mild except during occasional acute onset Wrist involvement Usual or common Rare, except in base of thumb metacarpal-carpal joint DIP = distal interphalangeal; MCP = metacarpophalangeal; PIP = proximal interphalangeal. Adapted from Bilka PJ: Physical examination of the arthritic patient. Bulletin on the Rheumatic Diseases 20:596–599, 1970.

Testing: The following tests are of particular importance:

• Arthrocentesis
• Serologic testing
• Usually ESR

Arthrocentesis is mandatory in most patients with a new effusion and can help rule out infection and crystal arthropathy as well as distinguish between an inflammatory and noninflammatory process. Other tests may be needed to identify specific disorders (see Table 5: Approach to the Patient With Joint Disease: Some Causes of Polyarticular Joint Pain).

If the specific diagnosis cannot be established clinically and if determining whether arthritis is inflammatory may help determine the diagnosis, ESR and C-reactive protein may be done. A low ESR makes inflammatory causes (eg, rheumatic disease, gout, infection, vasculitis) less likely but does not rule them out. Elevated results argue more strongly for inflammation, but they are very nonspecific, particularly in older adults.

Once a diagnosis of a systemic disease is thought to be most likely, supportive serologic testing for antinuclear antibodies, dsDNA, rheumatoid factor, anti-cyclic citrullinated peptide, and antineutrophil cytoplasmic antibodies may assist in making the diagnosis.

Treatment

The underlying disorder is treated. Systemic diseases may require either immunosuppression or antibiotics as determined by the diagnosis. Joint inflammation is usually treated symptomatically with NSAIDs. Pain without inflammation is usually more safely treated with acetaminophen Some Trade Names
GENAPAP
TYLENOL
VALORIN
Click for Drug Monograph
. Joint immobilization with a splint or sling can sometimes relieve pain. Heat therapy may relieve muscle spasm around joints, and cold therapy may be analgesic in inflammatory joint diseases. For cases of chronic arthritis, continued physical activity is encouraged.

Geriatrics Essentials

Osteoarthritis is by far the most common cause of arthritis in older persons. RA most commonly begins between ages 30 and 40, but in up to 1/3 of patients, it develops after the age of 60. Because paraneoplastic phenomena also can cause inflammatory polyarthritis, cancer should be considered in older adults in whom new-onset RA is suspected.

Key Points

• The differential diagnosis of polyarticular joint can be narrowed by considering the number of joints affected, whether inflammation is present, and the presence of any extra-articular signs.
• Chronic arthritis is most often caused by juvenile idiopathic arthritis in children and osteoarthritis and RA in adults.
• Acute polyarticular arthritis is most often due to infection, gout, or a flare of rheumatic disease.
• Arthrocentesis is mandatory in most cases of a new effusion and can help rule out infection and crystal arthropathy as well as distinguish between an inflammatory and noninflammatory process.

Last full review/revision January 2009 by Jessica R. Berman, MD; Steven A. Paget, MD

Content last modified January 2009