Joint Pain OSCE - Rheumatoid Arthritis

Case Overview

• Age/Sex: 46-year-old female
• Occupation: Office worker (administrative assistant, frequent computer use)
• Setting: Primary care / outpatient clinic
• Chief complaint: "Painful joints"

Patient Script

Who I Am

I'm a 46-year-old woman who works at a desk job typing most of the day.

What Brings Me In

My hands and wrists have been painful and stiff for a few months and it's getting worse — I can't type like I used to.

My Story

For about 3 months I've had aching in both hands and wrists that started slowly. The pain is worse in the mornings — I have stiffness for about 60–90 minutes and then it eases a bit as I move around during the day. Over the last 6–8 weeks the swelling has become more noticeable — my knuckles feel swollen and the rings are tighter. The pain is mostly on the front of my hands around the small joints and the base of my fingers; it feels symmetrical in both hands. I sometimes wake up with tingling in my fingers at night, but that comes and goes. I can still type but I make more mistakes and need breaks because of pain and weakness.

Two months ago I went hiking and I think I may have had a tick bite though I didn’t see a bull’s-eye rash. I also had a bad cold about two weeks ago that went away on its own. My mother has "bad knees" and was told she has osteoarthritis.

My Medical Background

• Past medical history: mild seasonal allergies; no known chronic illnesses
• Medications: ibuprofen occasionally (up to 400 mg once or twice daily), occasional paracetamol; no regular prescription meds
• Allergies: No known drug allergies
• Social: works full-time at a computer, drinks alcohol socially (1–2 glasses/week), non-smoker
• Family history: mother with osteoarthritis of the knees; no family history of rheumatoid arthritis recorded

What I Think & Worry About

• I think something is wrong with my joints — maybe "arthritis."
• I worry I might not be able to keep doing my job or that this will get worse and I’ll lose my hand function.
• I'm worried it could be something serious like an infection from the tick bite or something I might pass to my children.

If You Ask Me About Other Symptoms...

• Fever/chills: "No fevers, I haven't felt feverish."
• Weight/appetite: "No significant weight loss; appetite okay."
• Skin: "No rashes that I noticed — just occasional dry skin on my elbows."
• Eyes/mouth: "Sometimes my eyes feel gritty but that could be allergies." (patient attributes to allergies)
• Morning symptoms: "Stiff for about an hour to an hour and a half, then it loosens up."
• Night symptoms/neuropathy: "Some tingling in my fingers at night, especially after long typing sessions."
• Large joint pains: "My knees ache sometimes when I walk a lot, but nothing like my hands."
• Recent infections: "I had a cold two weeks ago; it got better."

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Clinical Summary

Examination

• General: alert, comfortable at rest, afebrile (36.6°C)
• Vitals: BP 122/78 mmHg, HR 82/min, RR 14/min
• Musculoskeletal:
  • Symmetrical synovitis: swelling and tenderness of bilateral 2nd–5th MCP joints and PIP joints, worse in the wrists bilaterally
  • DIPs not involved; no Heberden or Bouchard nodes
  • Small (approx 1 cm) subcutaneous nodule over the extensor surface of the left elbow consistent with a rheumatoid nodule
  • Reduced grip strength; difficulty making a tight fist on examination
  • Tinel and Phalen tests at the wrist: negative
• Other systems: cardiorespiratory and abdominal exams unremarkable; no lymphadenopathy

Investigations

• CBC: Hb 11.4 g/dL (mild normocytic anemia), WBC 7.2 x10^9/L, platelets 420 x10^9/L (mild thrombocytosis)
• ESR: 48 mm/hr (elevated)
• CRP: 24 mg/L (elevated)
• Rheumatoid factor (RF): positive, titre 1:160
• Anti-CCP (anti-cyclic citrullinated peptide): 120 U/mL (positive; high)
• ANA: negative
• Serum uric acid: 4.8 mg/dL (normal)
• Renal and liver function: creatinine normal, ALT/AST within normal limits
• Hand/wrist X-rays: periarticular osteopenia, soft tissue swelling, early marginal erosions at the 2nd and 3rd MCP joints bilaterally
• (If relevant) Lyme serology: negative

Diagnosis

• Primary: Rheumatoid arthritis

  • Supported by: history of >1 hour morning stiffness, symmetrical small joint inflammatory arthritis involving MCPs/PIPs, raised inflammatory markers (ESR/CRP), positive RF and high-titre anti-CCP, and radiographic periarticular osteopenia with early marginal erosions.

• Differentials:

  • Osteoarthritis: less likely because of predominant small joint MCP/PIP inflammatory swelling, prolonged morning stiffness and systemic inflammatory markers; DIP joints and bony enlargement typical of OA are absent.
  • Psoriatic arthritis: less likely — no psoriasis or nail changes and pattern is symmetrical small-joint synovitis with positive serology.
  • Reactive/viral arthritis or Lyme arthritis: considered because of recent cold and possible tick exposure (red herrings) — typically present with oligoarthritis or monoarthritis and negative anti-CCP/RF; Lyme serology here is negative.
  • Carpal tunnel syndrome / overuse tendinopathy: may explain nocturnal tingling and occupational strain but does not account for symmetric MCP/PIP swelling, prolonged morning stiffness, systemic inflammation, or positive serology.

Management

• Explain diagnosis to patient: probable rheumatoid arthritis and need for rheumatology assessment; reassure regarding treatability but emphasize need for early treatment.
• Urgent rheumatology referral for assessment and initiation of disease-modifying therapy (aim within 2 weeks if possible).
• Symptomatic relief: trial of NSAID (if no contraindication) and short course of low-dose oral corticosteroid (e.g., prednisolone) as a bridging therapy while awaiting DMARDs; advise regular paracetamol as needed.
• Baseline investigations and screening prior to starting DMARDs (to be arranged before or with rheumatology): hepatitis B/C serology, TB screening (IGRA or chest X-ray), baseline FBC, LFTs, and renal function.
• Discuss likely first-line DMARD (methotrexate) with need for folic acid, contraception if applicable, and monitoring — to be organized by rheumatology.
• Occupational adjustments: ergonomic keyboard/structured breaks, referral to hand therapy/physiotherapy for splinting and exercises to maintain function.
• Vaccination review: update pneumococcal and influenza vaccines and consider others per rheumatology guidance before immunosuppression.
• Safety netting: advise return if fevers, rapid worsening, signs of infection, new rash, or new systemic symptoms.

Key Learning Points

• Prolonged morning stiffness (>1 hour), symmetrical small joint synovitis (MCPs/PIPs), and systemic inflammatory markers raise strong suspicion for rheumatoid arthritis.
• Anti-CCP is highly specific for RA and, together with RF and radiographic erosions, supports early diagnosis and prompt initiation of DMARD therapy to prevent joint damage.
• Beware red herrings (recent tick exposure, occupational overuse, family osteoarthritis): always correlate history, exam, serology, and imaging to reach the correct diagnosis.