Back to Basics: Arthritis


By, Courtney Martin PGY-2 


There is a broad differential for patient’s presenting with joint pain. Many different disease processes lead to these symptoms. In this review we will break up the various etiologies of arthralgias by the number of joints they impact.  


  • Monoarthritis= involving one joint 

  • Crystal Arthropathies 

  • Gout- needle-shaped, negatively birefringent crystals that are erosive 

  • Pseudogout- rhomboid shaped, positively birefringent crystals that lead to calcium deposits in joints  

  • Hemarthrosis 

  • Traumatic  

  • Spontaneous- consider working up these patients for coagulopathies  

  • Osteoarthritis- asymmetric, worse with exertion, better with rest, slow onset  

  • Lyme Disease- see below 

  • Avascular Necrosis- risk factors include sickle cell disease, radiation, decompression sickness, malignancy, steroid use, chronic alcohol abuse  

  • Tumor 

  • Septic Arthritis-  

  • 85% of non-gonococcal- staph aureus, strep pneumonia, salmonella (in sickle cell patients) 

  • Gonococcal  

  • Oligoarthritis= involving 2-3 joints  

  • Septic Arthritis  

  • 15% non-gonococcal arthritis  

  • Gonococcal arthritis 

  • Lyme Disease 

  • Bacterial is borrelia burgdorferi- spirochete 

  • Transferred by ixodes scapularis tick  

  • Arthritis typically presents in late disseminated disease  

  • Rheumatic Fever  

  • Diagnosis made by Jones Criteria: 

  • Major Criteria: Arthritis, Carditis, Nodules, Erythema Marginatum, Sydenham Chorea 

  • Minor Criteria: PR prolongation on ECG, Arthralgias, ESR/CRP elevated, Elevated Temperature  

  • Reactive Arthritis   

  • Most common bacterial: Chlamydia, Ureaplasma, Salmonella, Shigella, Yersinia, Campylobacter, E. Coli  

  • Typically occurs 2-6 weeks after initial infection  

  • Combination of arthritis, urethritis, conjunctivitis  

  • Polyarthritis= involving 3+ joints  

  • Rheumatoid Arthritis: symmetric, worse in the morning 

  • Lupus 

  • Typically symmetrical, worse in the morning, migratory, no joint erosion  

  • PIP>MCP>wrist>knee 

  • Chronic Osteoarthritis 

  • Serum Sickness/Serum Sickness-like Reactions 

  • Caused by type III hypersensitivity reactions with immune complex deposits  

  • Triggered by various drugs, vaccines, viruses  

  • Viral Arthritis  

  • Common viruses- parvovirus, hepatitis B, hepatitis C, rubella, EBV, HIV, alphavirus  


Aletha D, Neogi T, Silman AJ, et al. 2010 rheumatoid arthritis classification criteria: an American College of Rheumatology/European League Against Rheumatism collaborative initiative.  Ann Rheum Dis 2010;69:1580.

Burton JH, Fortuna TJ. (2016). Section 23: Musculoskeletal Disorders, Chapter 284: Joints and Bursae.  In Tintinalli's emergency medicine: A comprehensive study guide (8th ed., pp 1927-1936). New York, NY: McGraw Hill Education.

Suhrbier A, La Linn M.  Clinical and pathologic aspects of arthritis due to Ross River virus and other alphaviruses. Curr Opin Rhematol 2004; 16:347.