Effect of internal fixation of the sternum using bioabsorbable pins in small children

OBJECTIVES: A sternal pin can be used to internally fix the reapproximated sternum after midline sternotomy. This paper will evaluate the effectiveness of using a sternal pin in small children by means of a computer tomography scan. METHODS: Propensity score matching was performed for patients undergoing a first-time median sternotomy from April 2012 to December 2014 with a follow-up computer tomography scan after 6 months. Seventeen matched patients were selected for both the control and the sternal pin groups. The angle of the sternal reflection at the joint surface was measured by computer tomography scan. In addition, the Haller index was measured at each thoracic vertebral level. RESULTS: The angle of the sternal reflection was more variable in the control group compared with the sternal pin group: the standard deviation was 31.6° for the control group and 10.2° for the sternal pin group (P value = .0009). Seven out of 17 patients in the control group had a negative angle (excavated sternum) compared with 1 out of 17 in the sternal pin group (P = .0391). In the other patients, the angle was 23.9° ± 3.6° in the control group and 10.1 ± 2.8 in the sternal pin group (P = .0061). The Haller index was also more variable in the control group, and it was significantly different from the sternal pin group at the ninth vertebral level (P = .0409). CONCLUSIONS: The study demonstrated that the use of a sternal pin was associated with decreased variation in the sternal angles and decreased incidence and severity of sternal protrusion and excavation in small children.