II. Definitions
- Arthritis
- Joint inflammation
- Arthralgia
- Joint Pain without inflammation
III. History: General
- See Monoarticular Arthritis
- See Polyarticular Arthritis
- Duration
- Acute (<2 to 6 weeks of symptoms)
- Subacute (2 to 6 weeks of symptoms)
- Chronic (>6 weeks of symptoms)
- Number of joints involved
- Monoarticular Arthritis
- Pauciarticular (Oligoarticular, 2-4 joints involved)
- Polyarticular Arthritis
- Migratory Arthritis
- Symmetric or Asymmetric (Polyarticular)
- Symmetric Polyarticular Arthritis
- Asymmetric Polyarticular Arthritis
- Course
- Intermittent
- Constant
- Distribution
- Spine and sacroiliac joints
- Medium and large joints (Shoulder, elbows, hips, knees)
- Small joints (wrists, fingers, toes)
- Joint inflammatory findings (synovitis or inflammatory Arthritis)
- Joint Swelling
- Joint erythema
- Prolonged morning Joint Stiffness (>1 hour)
- Pain and stiffness is better with activity and worse with rest
- Symmetric Polyarthritis
IV. History: Exposures and past medical history
- Triggers
- Joint Trauma (e.g. Traumatic Arthrotomy)
- Overuse
- Underlying conditions
- Prior affected joint surgery or procedures
- Infectious Disease
- Drug Induced lupus examples
V. History: Red Flags
-
Septic Joint Symptoms
- Fever
- Fatigue
- Weight loss
- Night Sweats
VI. History: Systemic Inflammatory Findings
- Rashes
- Oral Ulcers and Genital Ulcers
- Raynaud Phenomenon
- Serositis with Pleurisy or Pericarditis
- Sicca Syndrome with Dry Eyes (Xerophthalmia) or Dry Mouth (Xerostomia)
- Bowel inflammation (Enteropathic Arthritis)
- Vasculitis (e.g. CVA or TIA)
- Dactylitis (Sausage Digit)
VII. Exam: Distinguish pain source
- Articular (e.g. Arthritis, synovitis, joint contractures)
- Painful and reduced active AND passive range of motion
- Inflammatory Arthritis (red, warm, swollen, tender joints)
- Noninflammatory Arthritis
- Nonarticular or Periarticular (e.g. Muscles and tendons, ligaments, bursa)
- Normal passive range of motion
- Painful and reduced active range of motion and weak resisted range of motion
- Evaluate overlying skin and bursa
VIII. Labs: First Line
- Complete Blood Count (CBC)
-
Synovial Fluid Exam (Joint Aspiration)
- Single most important test
- Diagnoses Septic Arthritis as well as crystal Arthropathy (gout, Pseudogout)
- See Synovial Fluid White Blood Cell Count
-
C-Reactive Protein
- More reliable acute phase reactant than ESR
- Erythrocyte Sedimentation Rate (ESR)
-
Antinuclear Antibody (ANA)
- Positive with many Rheumatologic Conditions
- Higher Specificity for SLE with High ANA titer, positive Anti-dsDNA and Anti-Sm
- Anti-Citrullinated Peptide Antibody
- Most specific for Rheumatoid Arthritis (especially erosive disease)
-
Rheumatoid Factor (RF)
- Nonspecific (positive for Hepatitis C, Tuberculosis, SBE, SLE, Vasvculitis)
- Serum Uric Acid
- Low Test Sensitivity and Test Specificity for gout
- Serum Uric Acid is often low in acute exacerbations, and high in unaffected patients
IX. Labs: Second-Line (consider)
- Additional Infectious Arthropathy labs
- Synovial biopsy indications (unclear cases)
- Sarcoidosis
- Tuberculosis
- Hemochromatosis
- Whipple Disease
- Rheumatoid Arthritis
- Skin or tissue biopsy indications
X. Evaluation
- Single joint involved
- See Monoarthritis for evaluation
- Multiple Joints WITH Synovitis (joint localized inflammation)
- See Polyarthritis for causes
- Symptoms >6 weeks suggests systemic Rheumatologic Condition
- Obtain first line labs above
- Consider second line labs as indicated
- Symptoms <6 weeks suggests Viral Arthritis (or early Rheumatologic Disease)
- Start with Complete Blood Count and Liver Function Tests
- Consider Viral Hepatitis Serology
- Consider Parvovirus B19 testing
- Consider Lyme Disease in endemic regions
- Consider first line labs above if persistent or severe symptoms
- Multiple Joints WITHOUT synovitis
- Consider Fibromyalgia if pain is localized to Tender Points
- Consider Osteoarthritis in sporadic Joint Pain
- Consider Non-Rheumatologic Differential Diagnosis (see Polyarthritis)
- Consider XRay of involved regions
- Labs to consider
XI. Imaging
- See XRay Changes in Rheumatic Conditions
- XRay
- Acute Monoarthritis
- XRay affected joint
- Initial XRay most often normal
- Polyarthritis
- XRay symptomatic joints or those most consistent with suspected condition
- Acute Monoarthritis
- CT or MRI of affected joint
- Not a first line study
- Use only for specific indications
- Joint Ultrasound
- May demonstrate joint erosions (e.g. Rheumatoid Arthritis)
XII. References
- Pujalte (2015) Am Fam Physician 92(1):35-41 [PubMed]
- Shmerling in Helfgott (2021) Evaluation of the adult with Polyarticular pain, UpToDate, accessed 5/11/2022