Stenosing tenosynovitis (often called trigger finger, trigger thumb, stenosing tenovaginitis) is a painful condition caused by the inflammation (tenosynovitis) and progressive restriction of the superficial and deep flexors fibrous tendon sheath adjacent to A1 pulley at a metacarpal head. Repetitive forceful compression, tensile stress, and resistive flexion, causes inflammation, swelling, and microtrauma, that results in thickening and stenosis (commonly a nodular formation) of the tendon distal to the pulley leading to a painful digital base, limitation of finger movements, triggering, snapping, locking, and deformity progressively.
Patients report a popping sound (at the PIP joint), morning stiffness with/without triggering, delayed and sometimes painful extension of the digit, and when more advanced, a locking position that requires manipulation to extends the affected finger. This condition more commonly affects the middle and ring fingers (occasionally the thumb), and the flexor rather than extensor tendons in the hand.
In rheumatic trigger finger (or in diabetes), more than one finger may be involved. Cases of stenosing peroneal tenosynovitis, have been reported where the patient presents with pain over the lateral malleolus, both with active and passive range of motion and no physical of radiographic evidence of instability.
Read more about Stenosing Tenosynovitis: Two Common Diagnoses Fall Into This Category, Causes, Clinical Presentation, Differential Diagnosis, Work Up, Imaging, Management