[Congenital pseudarthrosis of the clavicle in two siblings].

Congenital pseudarthrosis of the clavicle is a rare disorder of unknown etiology. Among nearly 200 cases hitherto reported, only a few cases have familial coexistence, and none are first-degree relatives. A nine-year old girl had complaints of weakness in the right arm and swelling in the right shoulder. On physical examination, a mass-like lesion in the right clavicle, abnormal clavicular movement, and asymmetric shoulders were noted. The range of motion of the shoulder was in normal range on both sides. A plain radiogram showed a defect in the diaphysis of the right clavicle and computed tomography showed discontinuity of the right clavicle. Similar clinical and radiologic findings were also detected in her younger sister who was three years old. None had a history of trauma, difficult delivery, or natal complication, any abnormal findings related to the musculoskeletal system, any abnormality in routine laboratory test results and genetic analysis. The diagnosis was made as congenital pseudarthrosis of the clavicle in both siblings. Since they had normal range of joint movements without pain, they were scheduled for clinical follow-up. To our knowledge, these two siblings are the first to be reported in the literature for having congenital pseudarthrosis of the clavicle.