A 67-year-old woman comes to the office due to right hand pain. For the past 3 months, she has had mild to moderate pain at the base of the thumb that is worse when working with hand tools in her garden. In addition, the patient has stiffness in the hands for 5-10 minutes after awakening. Medical history is notable for type 2 diabetes mellitus. She drinks 2 or 3 glasses of wine a day. Vital signs are normal. Examination shows tenderness at both the palmar and the dorsal aspects of the base of the thumb that is associated with hard enlargement at the carpometacarpal junction. X-ray of the hand is shown in the exhibit. Which of the following is the most likely diagnosis?

Question

A 67-year-old woman comes to the office due to right hand pain.  For the past 3 months, she has had mild to moderate pain at the base of the thumb that is worse when working with hand tools in her garden.  In addition, the patient has stiffness in the hands for 5-10 minutes after awakening.  Medical history is notable for type 2 diabetes mellitus.  She drinks 2 or 3 glasses of wine a day.  Vital signs are normal.  Examination shows tenderness at both the palmar and the dorsal aspects of the base of the thumb that is associated with hard enlargement at the carpometacarpal junction.  X-ray of the hand is shown in the exhibit.  Which of the following is the most likely diagnosis?

Quizplus · Accepted Answer

11ec25c8_d22f_d65a_bc81_3357be459741_MD0003_00 This patient has osteoarthritis (OA) at the first carpometacarpal (CMC) joint. Hand OA typically presents with chronic, progressive stiffness and pain that worsen when working with tools or performing fine motor tasks. Risk factors include age >40, repetitive joint stresses, diabetes mellitus, and excessive alcohol intake. Examination typically shows hard, periarticular enlargement, crepitus with movement, and mild tenderness. Other affected joints include the distal interphalangeal (DIP) and proximal interphalangeal (PIP), where bony enlargement classically manifests as Heberden and Bouchard nodes. X-ray reveals decreased joint space, subchondral sclerosis, and periarticular osteophytes. enlargement Heberden and Bouchard nodes X-ray (Choice A) Chronic osteomyelitis presents with erythema, swelling, and pain, often with an overlying ulcer or sinus tract. However, osteomyelitis typically occurs in the foot (only rarely in the hand), and bone destruction, rather than enlargement, is typical. (Choice B) Hemochromatosis can cause arthritis resembling OA, and although men are usually symptomatic before age 50, women often develop symptoms later. However, hemochromatosis predominantly affects the second and third metacarpophalangeal joints with hook-like osteophytes on the metacarpal heads; involvement of the CMC joints is rare. hook-like osteophytes (Choice D) Psoriatic arthritis (PsA) typically presents with inflammatory arthritis that may involve the entire digit (ie, dactylitis). Symptoms are commonly cyclical/episodic rather than chronic/slowly progressive. Prolonged (>30 min) morning stiffness and pain lessen, not worsen, with activity. PsA commonly involves the DIP and PIP joints; CMC arthritis is atypical. X-ray reveals narrowing of the proximal phalanx with erosion of the distal phalanx (pencil-in-cup deformity) and new bone formation. It is uncommon (<10% of cases) for PsA to present before skin symptoms. pencil-in-cup deformity (Choice E) Rheumatoid arthritis commonly affects the hands, but usually affects the metacarpophalangeal joints and wrists. Swelling is typically firm or rubbery rather than hard and bony. Morning stiffness lasts >30 minutes; this patient's brief stiffness is more typical of OA. (Choice F) Gouty tophi involving the joint capsule, articular cartilage, or ligament insertions may cause pain with a hard mass adjacent to the joint. X-ray typically reveals soft tissue opacification and punched-out lytic lesions with a rim of overhanging bone (rat-bite lesion). Most patients have a history of acute, episodic gout. rat-bite lesion Educational objective: Osteoarthritis of the hands presents with hard, periarticular enlargement of the joints; crepitus with range of motion; and mild tenderness. It most commonly involves the first carpometacarpal joint and distal and proximal interphalangeal joints. X-ray reveals decreased joint space, subchondral sclerosis, and periarticular osteophytes.

A 67-Year-Old Woman Comes to the Office Due to Right