Primary Closure of a Subtotal Sternal Cleft in a 7-Day-Old Neonate

Sternal cleft is a rare congenital abnormality that results from incomplete fusion of the two lateral mesodermal sternal bars. It is generally accepted that primary repair in the neonatal period is the best treatment option. However, significant distance between the sternal bars can be challenging because of cardiac compression. The aim. We report a case of a 7-day-old neonate with a subtotal sternal cleft successfully managed by direct closure. Material and methods. A full-term male neonate weighing 3 kg was referred to our clinic for evaluation of a chest wall defect. The chest X-ray and computed tomography were performed to evaluate the malformation. Results. Surgery was performed at the age of 7 days. Postoperative period was uneventful. The patient was discharged on the postoperative day 21. The first postoperative checkup after 3 months showed satisfactory cosmetic results and normal respiratory movements. Conclusion. Despite the significant diastasis between sternal bars, primary direct closure of the sternal cleft can be safely performed in neonates.

a chest wall defect. Examination revealed U-shaped defect in the central part of the chest wall covered by the skin (Fig. 1).
The beating heart was visible through the skin. The chest X-ray and computed tomography revealed SC with no ossification center over the sternal area (Fig. 2).
Echocardiography ruled out intracardiac defects. Surgery was performed at the age of 7 days. An upper midline incision was made over the defect. The subcutaneous tissue was densely adjoined to the pericardium. The skin, subcutaneous tissue and superficial fascia were separated from the pericardium.
Thymectomy was performed to increase the capacity of the mediastinal cavity. The distance between the sternal bars was 5 cm (Fig. 3).
The inferior sternal bar was divided with subsequent mobilization of the sternal edges from both sides. In addition, U-shaped defect was converted to a 'V' by a careful wedge osteotomy in the xiphoid region. The two sternal bars were approximated by multiple intercostal PDS (polydioxanone) sutures which were pulled together but not tied (Fig. 4).
Heart rate, systolic blood pressure, central venous pressure, oxygen saturation, tidal volume, and airway pressure were monitored for ten minutes. All the aforementioned parameters remained stable. The PDS sutures were then tied (Fig. 5). The wound was closed in a standard manner.
Results. Post-operatively, muscle relaxants were continued during the first 24 postoperative hours in order to exclude any possibility for intra-thoracic pressure rise. Mechanical ventilation lasted 5 postoperative days for achieving good tolerance of the intrathoracic pressures. The recovery was uneventful. The patient was discharged on the postoperative day 21. The first postoperative checkup after 3 months showed satisfactory cosmetic results and normal respiratory movements (Fig. 6).   Comment. The sternal cleft is a rare congenital malformation: only about 100 cases have been previously reported in the literature [1]. Among numerous classification schemes have been described we found that the most accurate and applicable for our case was proposed by Fokin et al. [2]. In addition to partial (superior and inferior) and complete SC, the authors distinguish subtotal SC which is characterized by connection of sternal bars only at the bottom by a narrow bridge of tissue. The latter was observed in our patient.
Multiple surgical options for SC repair have been reported: primary approximation of the sternal bars, repair with autogenous tissues and prosthetic closure [4,5,8,10].
It's widely accepted opinion by now that the best treatment option is a primary direct closure which should be performed in the neonatal age because the chest wall in a newborn is relatively malleable [3,9].
More complex reconstruction with autogenous tissues or prosthetic closure is generally used in infants and older children. In addition, these techniques could be a method of choice in difficult cases in neonates. Ballouhey et al. managed a SC in an infant with a double osteochondroplasty flap [6]. Semlacher et al. reported a case of neonate with SC where the sternum was reconstructed with a synthetic mesh which was removed 21 days after surgery due to infection. Subsequently, the sternum was repaired using a porcine acellular dermal matrix [5].
In our case, given the significant distance between sternal bars (5 cm), we have considered multistage surgical repair with a gradual approximation of the sternal bars by simple suturing during each stage, as it was proposed by Baqain et al. [7], as a "theoretical approach, not yet reported". It would be an option of choice if the patient did not tolerate direct suturing.
Finally, close monitoring for 10 minutes during the intervention before the sutures tying helped to determine that direct closure is achievable without cardiovascular compromise.
Conclusion. Despite the significant diastasis between sternal bars, primary direct closure of the sternal cleft can be safely performed in neonates.
Authors' Note. Consent to publish this case report was obtained from the patient's family.