An Uncommon Etiology for a Common Condition: Giant Cell Tumor of the Tendon Sheath Presenting as Trigger Finger: A Case Report and Review of the Literature.

Introduction: Trigger finger is a common orthopedic condition that predominantly affects middle-aged individuals. Treatment modalities range from conservative measures like corticosteroid injections to surgical intervention depending on the severity, clinical presentation, and underlying etiology. Case Report: A 79-year-old female presented with triggering of her middle finger. After conservative treatment failed, further investigation revealed that the condition was caused by a giant cell tumor of the tendon sheath. Surgical excision and reconstruction were performed, resulting in satisfactory clinical outcomes with a full range of motion on follow-up. Conclusion: This case underscores the importance of considering rare causes for trigger finger, such as tumors, and highlights the need for thorough diagnostic evaluations in persistent or atypical cases of hand pathology.