Cognitive Bias: A Rheumatologic Disorder Disguised as Musculoskeletal Injuries Regan E. Malcolm, MD UNMC Department of Family Medicine/Offutt Air Force Base Family Medicine Residency, Omaha, NE
Introduction Family physicians must question their assumptions and consider a broader Diagnostic Imaging Outcome differential when symptoms arise that are not consistent with an initial diagnosis. ● Diagnosed with rheumatoid arthritis. Rheumatologic joint pains have significant overlap with musculoskeletal overuse injuries. ● Started on extended taper of prednisone and evaluated for suitability for methotrexate therapy while awaiting rheumatology consultation. Rheumatoid arthritis (RA) is a clinical diagnosis that relies on symptom pattern, physical exam findings, and lab and imaging findings [1]. Diagnosis takes into ● Symptoms improved rapidly with glucocorticoid administration. account: ● Joint involvement ● Serology ● Acute phase reactants ● Duration of symptoms [2]
Extra-articular manifestations occur in 8% to 40% of patients, including accelerated atherosclerosis, interstitial lung disease, pleural effusion, rheumatoid nodules, and others [3]. Patients with RA are additionally at increased risk for venous Discussion and Conclusions thromboembolism [4]. ● This case represented a delay in the diagnosis of rheumatoid arthritis due to confirmation and anchoring biases in the setting of confounding musculoskeletal complaints.
Figure 1: Non-occlusive thrombus mid-left subclavian vein. ● Rheumatologic joint pains can mimic musculoskeletal injuries. This patient’s job Case Report required repetitive, manual labor, in which musculoskeletal issues are common.
● 39 year-old female, employed in a job requiring manual labor and many hours on ● It is possible that patient had musculoskeletal injuries on top of underlying her feet, presented to primary care clinic with bilateral foot pain. rheumatoid arthritis.
● Physical exam testing was consistent with plantar fasciitis, de Quervain ● Initially diagnosed with plantar fasciitis and started physical therapy with tenosynovitis, and lateral epicondylitis. Although it is possible that the patient had improvement in symptoms. each of these different musculoskeletal issues, Occam’s razor reminds us of the Diagnostic Imaging wisdom of looking for a unifying explanation. ● Returned with left elbow and wrist pain a few weeks later, which was attributed to repetitive lifting and supination activities at work. ● Change in character of the pain to a generalized, full-body nature prompted further laboratory and radiologic investigation. ● Diagnosed with de Quervain tenosynovitis and lateral epicondylitis. Was given ● When multiple ailments present within short intervals of each other, it is wise to work activity modifications and again returned to physical therapy. look for a unifying etiology.
● Over the next month, developed aching sensation in shoulder. Doppler ultrasound revealed a non-occlusive thrombus in her mid-left subclavian vein. Started on Eliquis.
● Soon after, she developed diffuse full body pain leading to difficulty walking or gripping a steering wheel. References 1. Sparks JA. Rheumatoid Arthritis. Annals of Internal Medicine. 2019 ● ESR normal. CRP elevated to 1.7 (normal 0.01-0.9). Rheumatoid factor elevated Jan;170(1):ITC1-ITC16. to 32.5 (normal 0-13.9). Ferritin elevated to 407 (normal 15-150). Lupus 2. Aletaha D, et al. 2010 Rheumatoid arthritis classification criteria: an American College of Rheumatology/European League Against Rheumatism collaborative anticoagulant and autoantibody panels negative. initiative. Arthritis & Rheumatology. 2010 Sep;62(9):2569-81. 3. Wasserman A. Rheumatoid Arthritis: Common Questions About Diagnosis and Management. Am Fam Physician. 2018 Apr;97(7):455-462. Figures 2 and 3: Bilateral hand x-rays assessing for erosive joint 4. Holmqvist ME, et al. Risk of venous thromboembolism in patients with changes (none found). rheumatoid arthritis and association with disease duration and hospitalization. JAMA. 2012 Oct;308(13):1350-6.