Differential Diagnosis for Knot and Pain at Thumb
- Single most likely diagnosis
- Trigger thumb (Stenosing tenosynovitis): This condition is characterized by a knot or nodule at the base of the thumb, pain, and sometimes a triggering or snapping sensation when moving the thumb. It's a common condition that affects the tendon sheath, making it a likely cause for the symptoms described.
- Other Likely diagnoses
- De Quervain's tenosynovitis: This condition affects the tendons on the thumb side of the wrist, leading to pain and swelling, especially when forming a fist, grasping, or turning the wrist. It could be considered if the pain is more localized to the wrist area near the thumb.
- Ganglion cyst: A lump or mass that can occur near joints or tendons, often on the wrist but can also appear near the thumb, causing pain and discomfort.
- Thumb sprain: An injury to the ligaments surrounding the thumb, which can cause pain, swelling, and limited mobility, potentially feeling like a knot if there's significant swelling.
- Do Not Miss (ddxs that may not be likely, but would be deadly if missed.)
- Infection (e.g., abscess or cellulitis): Although less common, an infection in the thumb area could present with pain, swelling, and possibly a palpable knot. Missing this diagnosis could lead to serious complications, including sepsis.
- Tumor: A rare possibility, but a tumor (benign or malignant) could present as a knot or lump in the thumb area, accompanied by pain. Early detection is crucial for effective treatment.
- Rare diagnoses
- Giant cell tumor of the tendon sheath: A rare, benign tumor that can occur in the tendon sheaths of the thumb, causing a palpable mass and pain.
- Osteoid osteoma: A small, benign bone tumor that can occur in any bone, including those in the thumb, causing pain that is typically worse at night and relieved by nonsteroidal anti-inflammatory drugs (NSAIDs).