Differential Diagnosis for Intermittent Swelling between First and Second Metacarpal on Dorsal Aspect

• Single Most Likely Diagnosis
  • Ganglion cyst: This is the most common cause of a lump or swelling on the dorsal aspect of the hand, particularly between the first and second metacarpals. It is a benign cystic lesion that arises from the joint or tendon sheath.
• Other Likely Diagnoses
  • De Quervain's tenosynovitis: This condition involves inflammation of the tendon sheath on the dorsal aspect of the wrist, which can cause swelling and pain in the area between the first and second metacarpals.
  • Extensor tendonitis: Inflammation of the extensor tendons on the dorsal aspect of the hand can cause swelling and pain, particularly with activities that involve wrist extension.
  • Lipoma: A benign fatty tumor that can occur on the dorsal aspect of the hand, causing a soft, movable mass.
• Do Not Miss Diagnoses
  • Infection (e.g., abscess or cellulitis): Although less common, an infectious process can cause swelling and pain in this area, and it is crucial to diagnose and treat promptly to avoid serious complications.
  • Tumor (e.g., sarcoma): Although rare, a malignant tumor can present as a swelling on the dorsal aspect of the hand, and it is essential to consider this possibility to ensure timely diagnosis and treatment.
• Rare Diagnoses
  • Giant cell tumor of the tendon sheath: A rare, benign tumor that can occur on the dorsal aspect of the hand, causing a swelling or mass.
  • Rheumatoid nodule: A rare manifestation of rheumatoid arthritis, which can cause a swelling or nodule on the dorsal aspect of the hand.
  • Foreign body reaction: A rare cause of swelling and pain in this area, which can occur as a reaction to a foreign body (e.g., a splinter or other object) that has penetrated the skin.