A 58-year-old woman is evaluated for a 2-year history of hand pain and increasing difficulty using her hands. She reports worsening grip strength as well as increasing pain in the distal interphalangeal (DIP) and proximal interphalangeal (PIP) joints. She has intermittent erythema and swelling in some of these joints (such as the fifth DIP joint and the right second PIP and left third PIP joints) sometimes lasting for weeks at a time. She takes naproxen twice daily.
On physical examination, vital signs are normal. BMI is 29. Bony hypertrophy and malalignment of the DIP joints are noted; there is mild erythema over the right fifth DIP joint. There are bony hypertrophy of the PIP joints and swelling and tenderness of the right second PIP joint and the left third PIP joint. There is bony hypertrophy of the first carpometacarpal (CMC) joint bilaterally.
Laboratory studies, including a complete blood count, erythrocyte sedimentation rate, C-reactive protein, serum creatinine, rheumatoid factor, anti–cyclic citrullinated antibodies, and urinalysis, are normal.
Plain hand radiographs show central erosions and collapse of the subchondral bone in the right second PIP joint and the left third PIP joint; osteophytes at the second, third, and fifth DIP joints bilaterally; and joint-space narrowing at the first CMC joint bilaterally. There is no periarticular osteopenia or marginal erosions.
Which of the following is the most likely diagnosis?