Congenital pseudarthrosis of the clavicle in a 7-year-old girl: A case report treated with smooth elastic intramedullary pinning without bone grafting and literature review

The authors report a case of congenital pseudarthrosis of the right clavicle in a 7-year-old girl. It is a rare congenital malformation. Unanimity is far from being achieved on the best therapeutic method to adopt. This case benefited from a stable elastic medullary pinning without graft with an encouraging result. Case Report Congenital pseudarthrosis of the clavicle in a 7-year-old girl: A case report treated with smooth elastic intramedullary pinning without bone grafting and literature review Ibrahima Farikou1,2*, Handy Eone Daniel1, Fokam Pius2, Nana Chunteng Theophil1, Sosso Maurice Aurélien1 1Department of Surgery and Specialties, Faculty of Medical and Biomedical Sciences, University of Yaoundé I, Yaoundé, Cameroon 2Department of Orthopedic Surgery, Douala General Referral Hospital, Douala, Cameroon Dates: Received: 21 September, 2017; Accepted: 10 October, 2017; Published: 11 October, 2017 *Corresponding author: Ibrahima Farikou, Department of Surgery and Specialties, Faculty of Medical and Biomedical Sciences, University of Yaoundé I, Yaoundé, Cameroon, Tel: (237)699870267, Fax :(237)222310579; E-mail: https://www.peertechz.com


Introduction
Congenital pseudarthrosis of the clavicle is a rare clinical entity. The literature reports to date only 200 clinical cases in the world. The fi rst known description of this pathology dates back to 1910. It is mostly described in girls and often affects the right clavicle. Bilateral, familial forms have been reported. The diagnosis is both clinical and radiological. Concensus is still far from clear to the therapeutic attitude to adopt. We report the case of a 7-year-old girl, the fi rst one encountered in our practice for nearly 20 years, and the second case described in Africa to the best of our knowledge. We treated it surgically with a satisfactory anatomical and functional result.

Case Presentation
We report the case of a 7-year-old girl borne normally at term but with a low birth weight of 2,200kg. There is no family history of this pathology among the parents and sibblings. She was brought by her parents to our outpatient department complaining of pain and swelling of the left wrist without prior trauma. On the systematic examination of this girl, a swelling of the posterior aspect of the left wrist strongly suggesting a synovial cyst was noticed. On further examination, we noticed a swelling around the middle 1/3 of the right clavicle visible and palpable under the skin. The parents reported that this swelling has been existing since the birth of the child. (Figure 1).
The comparative radiographic assessment of the two wrists showed no bone pathology ( Figure 2). However, the comparative x-ray of the 2 clavicles revealed a congenital pseudarthrosis of the right clavicle ( Figure 3).
We prescribed an analgesic treatment to relieve the pain caused by the left wrist cyst. We as well suggested and discussed surgical treatment of this pseudoarthrosis of the clavicle and explained its necessity if she complains of pain, functional or aesthetic discomfort. We reviewed this child after about 1 year, complaining of an aesthetic discomfort that became more and more apparent as the child grew up. We then proposed surgical treatment and discussed it with the parents.
The procedure consisted in performing a direct approach to the pseudarthrosis focus under general anesthesia. We then excised the fi brosis exposing the fresh ends of the bone fragments followed by reduction and internal fi xation with smooth fl exible intramedullary pins (Figure 4), this construct was supplemented by an immobilization of the shoulder with an elbow-to-body sling.
The shoulder sling was removed 6 weeks after surgery.
The clinical evolution was marked by a satisfactory consolidation of the pseudarthrosis focus, this motivated us to perform implant removal on day 305 postoperatively. The radiograph of the clavicle done on day 435 shows a complete consolidation of the pseudarthrosis focus ( Figure 5).

Epidemiological aspect
The most important published series emphasized the predominance of the female sex: 0.3 and 0.8 respectively according to Cadilhac et al. [1], and Di Gennaro et al. [2]. The age of our patient, 7 years, corroborates with the average age of diagnosis of congenital pseudarthrosis which varies from 7.1 years on average for Studer et al. [3] to 11.5 years for Cadilhac et al. [1].

Aetiological aspect
Congenital pseudarthrosis of the clavicle is due, according to Lloyd-Roberts et al. [4], to a defect of fusion of the 2 points of ossifi cation of the clavicle. But the real mechanism of the origin of this pathology is unknown. The theory advanced by these authors would be the constant and abnormally high pressure exerted by the subclavian artery which is normally high on the right side. This pressure could be increased by the presence of the fi rst ribs on this side.
The rare involvement of the left clavicle would be linked to a dextrocardia and the existence of an abnormally large cervical rib. Lombard [5] also evokes a malposition of the fetus.
The familial cases reported by Cadilhac et al. [1], and Price et al. [6], and in twins by Akman et al. [7] suggest a genetic cause.

Clinical aspect
Pseudarthrosis of the clavicle is most often an incidental discovery [8] as in our case, and rarely symptomatic. It can be revealed by pain, neurological disturbances [9] or by a disgraceful cosmetic appearance that leads parents to consult [10]. It rarely presents with complication such as the thoracic outlet syndrme [9, 11, 12 and 13]. This last eventuality would be the result of a long evolution in the adolescent or the adult age.
Gamier et al. [14] reported 3 arterial complications of thoracic paralysis syndrome and recommended Doppler ultrasound of the subclavian or selective arteriography. A simple comparative X-ray of the 2 clavicles often makes it possible to make the diagnosis of congenital pseudarthrosis. In case of doubt, a CT scan with 3D reconstruction images confi rms the diagnosis and helps in the choice of therapeutic methods [15]. However, congenital pseudarthrosis of the clavicle may have the appearance of post-traumatic pseudarthrosis. This eventuality, in addition to the asymptomatic aspect of our case, prompted us to observe our case for a few months before the surgical treatment which fi nally was very necessary to remedy the aesthetic prejudice.

Therapeutic aspect
Most authors agree on a therapeutic abstention in cases of asymptomatic pseudarthrosis with an acceptable cosmetic aspect [16,17]. The treatment modalities depend on the age and severity of congenital pseudarthrosis. Some authors recommend excision of the fi brosis, autologous cortico-    In our case we carried out a thorough excision of the fi brosis and internal fi xation with intramedullary pins according to the technique described by Métaizeau [25] reinforced by immobilization of the shoulder by a elbow-to-body sling, which made it possible to obtain adequate consolidation without complication.

Conclusion
The diagnosis of pseudarthrosis of the clavicle requires a complete history, a brief clinical examination to appreciate the symptomatic, functional and aesthetic repercussions.
Therapeutic abstention is still a part of the therapeutic arsenal, but literature and our case teach us that surgery in children can produce quite satisfactory results with very few complications.