Management of forearm deformities with ulnar shortening more than 15 mm caused by hereditary multiple osteochondromas

Treatment for forearm deformities caused by hereditary multiple osteochondromas is still controversial. The purpose of the study was to describe the outcome of treatment with the combined use of ulnar lengthening and excision of osteochondromas.

Fourteen patients with hereditary multiple osteochondromas had forearm deformities which belongs to type I Masada deformity. The mean relative ulnar shortening was 19.9 mm (range, 16-23). All patients ranging from 4 to 15 years old had operative treatment. Clinical evaluation involving the assessment of pain, activities of daily living, and range of motion of the wrist and forearm was performed. The radiographic evaluation was relative ulnar shortening (RUS), radial articular angle (RAA), carpal slip (CS), and radial bowing. Besides, we also evaluated the amount of ulnar lengthening, external fixation time, and external fixation index.

The mean EFT was 101 days (range, 84-133), and the mean external fixation index was 44.4 days/cm (range, 33.6-51.2). During the mean 43.1 months follow-up, four patients had mild pain and two patients had mild restriction of daily activities. The rotation of forearm and motion of wrist had increased except in Case 3. The RAA, CS, and radial bowing had been improved except in Case 6 and 7. In all patients, relative ulnar shortening had been corrected. According to the functional evaluation criteria recommended by Krimmer, there were ten excellent and four good.

The combined use of ulna lengthening and excision of osteochondromas is a proper and effective treatment method to the type I Masada deformity with the relative ulnar shortening more than 15 mm.