Trigger thumb, right thumb

This code represents stenosing tenosynovitis affecting the flexor tendon of the right thumb, characterized by inflammation and narrowing of the tendon sheath. This condition causes the thumb to catch or lock when bent, often accompanied by pain and a palpable nodule.

Apply this code when documentation clearly indicates a diagnosis of trigger thumb specifically affecting the right thumb. This diagnosis is typically made based on physical examination findings, such as a palpable nodule, tenderness, and a "catching" or "locking" sensation during thumb flexion and extension.

• Ensure laterality is explicitly documented as "right thumb" to support this specific code.
• Do not confuse with other tenosynovitis codes affecting different digits or unspecified locations.
• Consider additional codes for associated pain (e.g., M79.641) if separately documented and treated.