Flexor Tendon Rupture after One Corticosteroid Injection in the Treatment of Trigger Finger: A Case Report and Literature Review.

Corticosteroid injection is a widely accepted first-line treatment for trigger finger. However, it carries a potential risk of flexor tendon rupture. This complication is rare, particularly after a single injection. We present a 59-year-old woman who experienced spontaneous ruptures of the flexor digitorum profundus and superficialis tendons of the middle finger 2 months after a single corticosteroid injection for trigger finger. We review the literature and discuss underlying mechanisms for flexor tendon rupture. To minimise the risk of this complication, we recommend administering extra-tendinous injection of corticosteroids at the lowest dose and advising patients to avoid strenuous activities, such as heavy gripping, sports or lifting, for at least 3 weeks post-injection. Level of Evidence: Level V (Therapeutic).