Purpose of the study: Congenital pseudarthrosis of the clavicle is rare, only 200 cases having been reported. Based on 25 personal cases and an overview of the literature, we try to explain the etiology of this condition and the different kinds of treatment.

Material and methods: A retrospective analysis was performed on twenty-five children (16 females, 9 males, mean age at the end of the follow up – 11.5 yrs) from three different centers. We assessed the outcome of surgical and nonsurgical procedures, based on pain, functional ability, cosmetic results, and x-ray examination.

Results: A family background was noted in three children. The lesion always involved the right side. Twenty patients presented a bump over the middle third of the clavicle, thirteen a foreshortened shoulder girdle, three complained of discomfort. In two cases, palpation of the clavicular area was painful. No neurovascular compressive syndrome was reported. None of the patients complained of a decrease in the range of motion or in the strength of the upper limb. X-rays showed a middle third defect. In five cases we found abnormal first ribs.

Seventeen patients underwent surgery, at a mean age of 6 years and 4 months. The procedure always included excision of the pseudarthrosis at both ends and internal fixation with a wire or a plate. In only eight cases a bone graft was used. Healing was achieved in fourteen patients. Three patients needed a second surgical procedure. In these 3 cases we had not used bone grafting. All patients had a normal range of shoulder motion, except a twelve year old girl who complained of discomfort of the right upper limb. The cosmetic result was good in eleven cases, one surgical wound was noted as hypertrophic, and one developed a keloid. An asymmetry of the trunk was still noted in seven cases. The x-rays showed symmetric clavicles in ten cases.

Eight patients were treated conservatively. All of them had a normal range of motion of the shoulder, six had a good cosmetic result and two cases a poor one.

Discussion

According to Alldred, the anomaly results from the failed coalescence of the two primary ossification centers of the clavicle. The overview of the literature and our findings (in one case) confirm that the cartilage which covers both ends of the bone is made of growth cartilage. However, the true mechanism of the nonunion is still unknown. The three familial cases of our work suggest a possible genetic transmission of the disease.

The diagnosis is based on the following criteria: right side lesion, found in infancy, without previous fracture, increasing size with growth, without major functional consequences, without neurofibromatosis or cleidocranial dysostosis symptom. X-rays or histologic examination will confirm the diagnosis showing the usual findings described above.

Complications of the pseudarthrosis of the clavicle are rare and late. Conservative management appears to give good results as seen with our eight patients. However surgical treatment ensures symmetrical shoulder girdles and good function with few complications. Therefore, we recommend performing an excision of the cartilaginous caps, followed by an iliac bone graft and an internal fixation with wire. Surgical management will be preferred in symptomatic patients, in the case of major or increasing deformity, or on parental request.