Dupuytren contracture is characterized by progressive thickening and tightening of which structure, leading to fixed flexion deformity at the MCP joint?

• A. Palmar fascia
• B. Pronator teres muscle
• C. Flexor tendon sheath
• D. Interosseous membrane

Answer: (A)

Dupuytren contracture arises from fibrous thickening of the palmar fascia, specifically the palmar aponeurosis. This myofibroblast-driven process creates cords and bands within the fascia that progressively pull the fingers into flexion at the metacarpophalangeal joints, often with less involvement of the joints themselves, leading to a fixed flexion deformity. The other structures listed—the pronator teres, the flexor tendon sheath, and the interosseous membrane—are not the tissues that undergo this fibromatosis and are not responsible for the MCP joint contracture seen in this condition.