Pathologic fracture of metacarpal enchondroma: case study and differential diagnosis.

Objective: To discuss a case of enchondroma initially appearing as a pathologic fracture in a metacarpal bone. The recommended treatment for a pathologic fracture of an enchondroma in the hand is reviewed. Additionally, a reasonable list of differential considerations is presented with accompanying radiographic and advanced imaging characteristics.

Clinical Features: A 25-year-old male chiropractic student had a painful, bruised, and swollen thumb following athletic trauma. Radiographs showed a pathologic comminuted fracture of the first metacarpal, with a resultant anterior angulation of the distal fragment. Fracture occurred through a well-defined, geographic, lucent lesion in the proximal metaphysis consistent with enchondroma.

Intervention And Outcome: Closed reduction of the fracture and casting were used. No treatment was administered for the enchondroma. Adequate healing of the fracture took place with residual angulation at the fracture site. Size and extent of the enchondroma were unchanged after fracture healing.

Conclusions: Recommended treatment for a pathologic fracture through an enchondroma in the hand is casting, which allows fracture healing. Curettage of the lesion without packing of the resultant cavity is then recommended. In this case, casting and fracture healing took place without any treatment directed at the enchondroma. The patient was advised of the rationale for undergoing the removal of the enchondroma. Removal was recommended to prevent fracture recurrence from structural weakening, which would be likely due to the unusually high level of mechanical stress from the professional demands of manual treatment.