Rationale: Fibroma of tendon sheath is a rare entity that is typically attached to the tendon sheath.
Patient concerns: A 43-year-old man presented with a painful mass in his right wrist, which was initially misdiagnosed as an enchondroma.
Diagnosis: Fibroma embedded into carpal bones, which exhibited lytic radiographic features similar to those of enchondroma. Excisional biopsy demonstrated spindle-shaped cells and collagen-like stroma.
Interventions: The patient underwent lesion resection surgery.
Outcomes: The patient recovered well and showed no signs of recurrence at 6-month follow-up.
Lessons: This case provides valuable insights for hand surgeons. While radiograph is helpful in multiple diseases, histological examination is indispensable for establishment of final diagnosis.