Focal Fibrocartilaginous Dysplasia in the Ulna: Report on 3 Cases

Focal fibrocartilaginous dysplasia is an uncommon, benign bone lesion that causes deformity in young children. It is most commonly encountered in the proximal tibia, with few cases documented in the upper extremity. We report 3 cases affecting the ulna. In each case, the fibrous tissue appeared to anchor itself in the ulnar diaphysis, behaving as a tether that retards growth. All 3 patients had excision of the fibrous tissue. There was concern for radial head subluxation before surgical intervention, but all patients maintained a congruent radiocapitellar articulation. The visible deformity improved in all 3 patients, although the limbs remained shorter than the contralateral side. In our limited series, we believe that early excision of the fibrous tissue tether can prevent radiocapitellar joint dislocation in patients with focal fibrocartilaginous dysplasia of the ulna.