A 17-year-old female with bilateral congenital trigger thumb diagnosed in late adolescence: a rare case report.

Introduction and importance: Congenital trigger thumb, affecting approximately 0.3% of children, is characterized by a locked interphalangeal joint and can result from a mismatch between the flexor tendon and thumb pulley system. Though typically diagnosed in early childhood, late diagnosis can occur, as demonstrated in this case. Understanding the differential diagnoses and clinical presentation of trigger thumb is crucial for effective management, particularly when symptoms persist into adolescence.

Case presentation: A 17-year-old female presented with a long-standing inability to hold a pen due to a flexion contracture of both thumbs, preventing full extension of the metacarpophalangeal joints. Despite the condition's presence since childhood, it had not been diagnosed until adolescence. Radiographs revealed excessive extension at the carpometacarpal joints. The patient had no significant medical history or accompanying symptoms.

Clinical discussion: This case highlights an unusual presentation of congenital trigger thumb diagnosed in late adolescence. Typically identified in infancy, late diagnoses may complicate early treatment and long-term management. Surgical intervention, including the A1 pulley release, effectively restored thumb function and resolved the deformity. This case underscores the importance of considering congenital trigger thumb in older children or adolescents with unexplained thumb deformities.

Conclusion: Late diagnosis of trigger thumb is rare but important to recognize, as timely surgical intervention can effectively restore functionality. Awareness of this condition beyond infancy is essential for comprehensive clinical care.