Diagnosis of TF is primarily made based on history and physical examination. Patients with TF often present with pain or clicking at the level of the metacarpal head that causes limitation in grasping and holding objects. In more advanced cases, patients report locking or catching of the digit in addition to loss of motion at the MCP joint and the PIP joint. Patients with early TF may have only swelling and tenderness to palpation of the A1 pulley, whereas those presenting later may have a palpable nodule and palpable clicking that is reproduced with flexion and extension of the involved digit and is exacerbated with simultaneous compression of the A1 pulley. In early trigger thumb, symptoms are often reported at the interphalangeal joint. Pathology at the tendon-pulley interface can be demonstrated with ultrasonography evaluation if needed to confirm the diagnosis.
J Am Acad Orthop Surg. 2020;28(15):e642-e650. © 2020 American Academy of Orthopaedic Surgeons