Xeljanz®(tofacitinib citrate) Prescribing information, Enbrel®(etanercept) Prescribing information, Inflectra (infliximab) Prescribing information and Maxtrex(methotrexate) Prescribing information. Adverse event reporting can be found at the bottom of the page.

The physical features of RA manifest inside and outside of the joints. These are sometimes referred to as articular and extra-articular manifestations, respectively.⁵ In addition, patients with RA have a higher risk of having certain other diseases.⁸ Co-occurring diseases are referred to as comorbidities.⁸ Before we describe the manifestations of RA, let’s go over some terminology to discuss joints.

Joints of the fingers and toes are named based on the bones that meet to make the joint. In the diagrams below, bones are labeled on the left and joints are labeled on the right. Notice that the bones of both the fingers and toes are called phalanges (the singular form of the word phalanges is phalanx). Fingers and toes each have three phalanges except for the big toe and thumb, both of which have two phalanges (ie, no middle phalanx). 

• Smaller joints that are commonly affected include the metacarpophalangeal joints, proximal interphalangeal joints, joints of the wrist, and metatarsophalangeal joints.¹

• ​​​​​Larger joints that may be affected include elbows, shoulders, cervical spine (neck), hips, knees, and ankles.^1,5

• The number and location of involved joints varies across patients.¹

• Deformities can occur over time in the form of  partial dislocations (referred to as subluxations), deformed positions of joints (such as swan neck deformity, boutonniere deformity), and ruptured tendons.^3,5

1 - Aletaha 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; 69:1580-1588.
3 - Stedman’s medical dictionary for the health profession and nursing: Baltimore Maryland: Lippincott Williams & Wilkins. Illustrated 5th ed. 2005.
5 - Khurana R, Berney SM. Clinical aspects of rheumatoid arthritis. Pathophysiology. 2005; 12:153-165.
8 - Gabriel SE, Michaud K. Epidemiological studies in incidence, prevalence, mortality, and comorbidity of the rheumatic diseases. Arthritis Res Ther. 2009; 11(3):229. doi:10.1186/ar2669.
22 - Standring S ed. Pelvic girdle and lower limb: overview and surface anatomy. In: Standring S. ed. Gray’s Anatomy: The Anatomical Basis of Clinical Practice. 41st ed. Chapter 78. Elsevier Limited. 2016. p. 1316-1333.
23 - Gibofsky A. Overview of epidemiology, pathophysiology, and diagnosis of rheumatoid arthritis. Am J Manag Care. 2012; 18(13):S295-S302.
24 - Dougados M, Soubrier M, Antunez A, et al. Prevalence of comorbidities in rheumatoid arthritis and evaluation of their monitoring: results of an international, cross-sectional study (COMORA). Ann Rheum Dis. 2014; 73:62-68.